A/N: So, yes, I am once again making a liar out of myself. The minute I saw a still of Arthur Darvill recording the voiceover for "P.S." I suspected another chapter of "Father's Day" would be necessary, and sure enough, the plot bunnies attacked. If you haven't seen "P.S." yet, it's available at the BBC One website.

Chapter 5: Siblings

Last year, River thought, it was raining.

As she stood outside Brian Williams' door, River considered the possibility that the weather was trying to tell her something. The last time she'd seen her grandfather it had been their first meeting since losing Amy and Rory. Father's Day had always been bittersweet for her - even after she'd finally been able to tell Rory who she really was. Experiencing the day without him for the first time had been emotionally draining, and the rain had felt only appropriate. Today, however, the sun was shining, and an unfamiliar car was parked on the street.

She couldn't be certain until she rang the bell, but River had a pretty good idea of whose car it was.

"This was so much easier back when I was the only one with secrets," she muttered under her breath as she raised her hand to ring the bell.

Brian had been waiting for the bell to ring. He'd been anxious all morning, spilling tea and burning toast, but when Anthony had asked if anything was wrong he'd merely brushed off the question. When the buzzer finally sounded, he knocked over his chair in a rush to get to the door. Anthony didn't follow - if the person on the other side of that door was who he suspected, she would come to him.

"You came," he heard his grandfather say faintly from the entryway, and a soft feminine laugh followed.

"Of course I came. Don't I always?" the voices grew louder - they were headed toward the kitchen.

Anthony Williams was not an anxious man by nature. The secrets this house now held had been with him since he was a boy. He'd grown up with the knowledge that his family wasn't traditional in any sense of the word. Today, he reminded himself firmly, was just another case-in-point. Besides which, Dad wouldn't have panicked at a time like this and neither would he.

"There's someone I'd like you to meet," Brian said, stepping into the kitchen again. Anthony stood. This was it, the moment he'd been waiting over sixty years for.

The woman who followed his grandfather looked exactly like his parents had always described her. Riotously curling hair, a knowing smile on her lips, eyes that danced, and incongruously formal clothing.

"Anthony, this is Dr. River Song." She held out her hand for him to shake, and for a brief moment Anthony wasn't certain she knew who he was. The tears he saw fill her eyes assured him that she most certainly did, though, and as the siblings clasped hands for the first time, he felt the prickling of his own.

"It's very nice to meet you, Anthony," she said. He was impressed by how steady she managed to keep her voice. He wasn't sure he could trust his own.

"River, do - do you know who he is?" Brian looked from one to the other uncertainly.

"I'm an archaeologist, Brian," she reminded him gently. "I know my way around a library. Anthony Brian Williams, born March 15, 1946. Adopted by Rory and Amy Williams March 23 of that same year. You're a teacher, I believe."

Anthony nodded and cleared his throat. "Dr. River Song: archaeologist, time traveler, and sometimes savior of the universe. You weren't in any libraries I ever saw, but I've heard stories about you for as long as I can remember. I don't think a day went by when Mom and Dad didn't mention you."

Brian's grin interrupted them both. "Splendid! And to think I was worried that we'd be spending the day making awkward explanations to one another. Well then, what shall we do?"

Anthony and River exchanged a look as Brian poured himself a new cup of tea. It was going to be an interesting day.

"Good shot, Brian!" River exclaimed, watching as Brian's ball sailed toward the green. As she lined up her own shot, she made a point of catching Anthony's eye. She winked, and hit the ball deliberately into the rough.

"Ouch! Nasty bit of business that'll be to get it out," Brian squinted. "You're usually a much better shot than that, River."

"Haven't been out for awhile - it's been a busy few months. Anthony, I believe it's your turn."

Anthony tightened his grip on his club. Golf had never really been his game, and he hoped he'd have enough control over the ball to get it reasonably close to River's. There were things they needed to discuss without Brian present, and this would be the perfect opportunity. Taking a deep breath he swung.

"Out of practice too, Anthony?" he heard his grandfather ask, and Anthony hoped his smile looked sheepish instead of guilty.

"A bit, yes. I've always been more of a tennis man, actually."

Brian shook his head. "Well, it's hardly a surprise. Do you remember the last time we were here, River? Rory lost three balls to the rough, one to the pond, and spent at least half an hour in the sand trap at the fourth hole. Like father, like son," He grinned broadly, and Anthony smiled in return to see his grandfather able to say his dad's name without looking as if his heart might break.

River smiled too, fondly at the memory "We were here until nightfall. Bless. Well, Brian, I think it's safe to say that it might take a few minutes for Anthony and I to get back to the green. Shall we meet you there?"

"Excellent idea," he began to re-pack his golf bag. "There's a drinks stand not too far off - I'll get us some waters."

"Ready?" she asked, turning to Anthony. He nodded. He'd been ready for this conversation for as long as he could remember.

"What did they tell you about me?" she asked as soon as they were out of Brian's earshot.

"The truth, once I was old enough to understand it. I know that you were born Melody Pond at a place called Demon's Run. That an alien religious order called the Silence kidnapped Mom after she got pregnant and created a double of her so she'd think she was on the TARDIS when she was actually sedated and held captive so they could take you after you were born. I know the Doctor tried to save you, but he was too late. I know you grew up with them - they were never really clear about how you got to Leadworth, though - and were called Mels Zucker. I know you tried to kill the Doctor once, and then gave your remaining regenerations to save his life. I know you married him, and were put in prison for killing him. He wasn't dead, but you stayed there so everyone would think he was. I know you saved their lives more than once, and that they loved you very, very much." Anthony had kept his eyes on the grass while he talked, but looked up to meet hers just as he finished.

River was looking back at him. "Yes, that just about covers it."

"How-" Anthony broke off. The question had been on the tip of his tongue since he'd first laid eyes on her, but now he was having trouble asking it. "How long have you know about me?"

"Not long." They had reached the rough now, and River took a deep breath as their pace slowed and stopped. "I made a point of not looking for them in history before... well, before Manhattan and the Angels. That was less than two years ago for me. Afterwards... well, it took awhile before I was ready to find out what happened to them. I didn't know about you the last time I visited Brian."

Anthony nodded slowly. From her perspective, the loss of their parents was still new enough to be raw. From his, they'd both been gone long enough for injury of grief to have mostly scarred over. He could think of them - talk about them - without feeling a painful twinge under his breastbone. He could tell she was still struggling to do the same.

"I wondered if you'd come to see me after Mom died," he said. "It makes sense now why you didn't. You didn't know then."

River shook her head. "I'm a time traveler, Anthony. And... well, a bit of a coward if you want to know the truth. I thought about going there, after I knew Amy had... the time lock around them was broken, I could have made the trip. I suppose I decided to come here instead because I thought it would be easier to meet you with Brian around."

Anthony decided to leave her comment about being a coward alone for the time being. "Speaking of, what do you want to tell him?"

"About what?" she looked genuinely confused.

"About you - me - that you're not just Mom and Dad's time traveling friend, you're also their daughter. My sister."

And there it was. The word neither of them had spoken up until this point. Sister. She was his sister. He was her brother. A lump rose in Anthony's throat, and he struggled to speak past it. "He should know, River. It's the right thing to do. You know it is."

A beat, and then River opened her mouth to respond. "Oh look, my ball," she pointed at a spot several feet away and started off towards it. Anthony, dumbfounded, stood in place for a moment, staring at the empty space where River had just been. "I think I see yours too," she called back to him.

"River!" he exclaimed, not bothering to keep his voice low in case Brian was nearby.

"Look, Anthony," her voice was quiet and soothing, but there was an undercurrent of steel there as well. "It's not that simple. Brian has known me for years. How am I supposed to explain to him that all this time I've been his granddaughter and never said a word? How do I tell him that Rory lied to him - for years? It would break his heart. No, it's better for everyone that I stay a somewhat enigmatic but very dear friend who also happens to be one of three other people in the universe who knows what really happened to his son and daughter-in-law."

Anthony shook his head, incredulous. A small voice in the back of his mind (a voice which sounded suspiciously like his mother) spoke up with a reminder that they had warned him that River kept secrets from everyone, and it was usually best to let her come forward with the truth in her own time. A louder voice argued that it was ridiculous to hang onto a secret this huge when telling it could only bring happiness to everyone involved.

"I don't agree," he said shortly. "I know this is how you live, but it's not right. Not now. He deserves to know."

"Anthony," she took his hand in her own. "I don't want to argue with you, but this isn't up for debate. Our parents," she took a sharp breath at "our" and Anthony suddenly realized that she was feeling just as overwhelmed by the day's events as he was. "Amy and Rory - they didn't want to tell him about me. The Doctor is the only other person alive who knows who I really am. That was their choice to make, not mine. I happen to think that it's the right one to keep making now, under the circumstances, but ultimately their wishes are the ones I'm honoring by letting Brian continue to think that I'm just a friend."

"That's not true," he said sharply. "You don't know the whole story, River. I do. They regretted keeping the secret. Dad talked about it whenever he mentioned either of you. 'We should have told him,' is exactly how he put it. I heard that for years, River. Yes, when you knew them they'd made the choice to keep you from him, but they changed their minds."

"Brian's going to come looking for us. We need to get back onto the course before he does." She turned, pulled a club out of her bag, and began to line up a shot.

"River!" he protested again. "Why won't you discuss this? If it was you, wouldn't you want to know?"

She didn't reply, but merely swung at the ball, easily sending it sailing back onto the green. Without a word, she slung her bag back onto her shoulder and started off after it.

"So, care to tell me what happened back there?" Brian asked Anthony after River had excused herself to the ladies room. They were perusing the menu at the club restaurant after a tense and mostly silent remainder of the golf game.

"Back where?" Anthony asked, trying to sound casual.

"Back on the rough. You and River went down there together and clearly got into some kind of argument. You didn't say two words to one another for the next six holes - did you think I wouldn't notice? What happened, Anthony?"

"It's... it's complicated. There were... things... I needed to ask her. Things about Mom and Dad. We had a difference of opinion, that's all. Please don't let it spoil your day." Anthony took the younger man's hand and smiled. "It's Father's Day. Don't worry about me and River - let's focus on celebrating you and Dad like we should."

"Yes, let's," said River, sliding into her seat next to Anthony. He hadn't even realized she was back. "I took the liberty of ordering some champagne." A waiter filled three flutes.

"To Brian Williams, a fantastic grandfather," she said, raising her glass. Anthony followed suit without a word. An odd expression settled onto Brian's face as he raised his own glass and tapped it lightly against theirs. And suddenly, Anthony understood. Brian knew. Neither his dad nor River had ever said a word, but Brian knew.

"And to Rory Williams, an equally fantastic father," Antony found himself saying as he looked River straight in the eye. "In every era."

They tapped glasses again and drank.

"Will you be staying?" Anthony asked River quietly as they sat together at Brian's kitchen table later that night. He'd gone up to bed, but had encouraged them to "have a nice chat."

"No. I used to stay-" she paused, then took a deep breath, "with Mum and Dad sometimes, but never with Brian. You'll be around for a few more days at least, though?"

"Yes, my flight back to New York doesn't leave until next Tuesday. Granddad is going to show me around town, and then we're heading to London for a few days. I've never been." He watched River out of the corner of his eye. "Where are you off to, then?"

"Home," she said simply.

"And where is that? The TARDIS?"

She smiled. "No, not usually. I have a house near the university. Luna University," she clarified. "Around three thousand years from now. I'm a professor there."

He nodded. "Do you like it?"

She smiled. It was the same fond smile she'd had when she was talking to Brian. "I do. Very much. And of course I'm not always there."

"The Doctor. I've never met him."

River shifted in her seat and looked him in the eye. "I don't know that you ever will, Anthony. He does know about you, and believe me when I say that he was more delighted than words can express when we realized that Amy and Rory had finally become parents. Real parents. But I think he's hesitant to meet you, only because he doesn't want to interfere in your life."

Anthony nodded. "It's all right. To be honest, he always sort of scared me when I was growing up. A time traveling alien who eats fish sticks and pudding?"

River laughed then, loudly enough that for a minute Anthony was worried she might have woken Brian. "Oh, he is going to love that."

"The truth is, River, the only people from my parents' past lives I was ever really interested in meeting were you and Granddad."

Her expression turned serious again. "The feeling is mutual, Anthony. I'm sorry about earlier. It's just that-"

"He already knows, doesn't he?" Anthony took her hand. "I could tell in the restaurant. He knows who you are."

"I'm not certain, but yes, I think he suspects." She rubbed a hand across her eyes, and Anthony was suddenly struck by the realization that in spite of the fact that she looked at least twenty years his junior, she was almost certainly several hundred years older than he was. Big sister, indeed, he thought to himself.

"So why not just tell him?"

She shook her head. "If I do, it means I also have to tell him where I was all those years. If I tell him that I'm his granddaughter he's going to have questions. I could lie, but if he asks I really don't think I have the will to keep the truth from him even though I know the answers will be very painful for him to hear. I don't know that either of us is ready for that. Maybe in the future, but not now."

"I still don't agree, but the decision is yours to make."

They sat in silence for a few minutes more.

"We did this once, Dad and me," she said simply. "It was right after they'd thought the Doctor died – right after we were married from their perspective – and I came on Father's Day to visit. We wound up getting drunk in the garden, and after he put Mum to bed he and I just sat in the kitchen and talked for hours."

Anthony smiled. "We did that too. Not, obviously, under the same circumstances, but the late-night talks in the kitchen. I remember once when I was in college I came home in the middle of the night. I went to NYU, so they were close enough to visit whenever I wanted or needed them. Anyway, I came home around two in the morning – I don't remember exactly why, just that it was a bad week and I think I needed the comfort of home – and there he was. It was almost like he was waiting for me. He didn't ask questions or push me to explain why I was there, he just made me a cup of tea and we talked about nothing for hours.

"Tell me about him?" River asked quietly.

And he did.

Brian crept down the corridor as quietly as he could. He didn't mean to eavesdrop – well, actually he did, and they were talking too softly for him to hear the conversation from the top of the stairs.

"He already knows, doesn't he?" he overheard Anthony ask.

Tears of mingled joy and sorrow began to flow from Brian Williams' eyes as he listened to his grandchildren begin the process of bonding with one another.

He loved them, and so he would let them keep their secrets because at the end of the day the things they said to him weren't what mattered. What mattered was that they came to terms with each other. Like all brothers and sisters, they needed to work out their differences on their own.

It wasn't a perfect Father's Day. It wasn't a perfect family. But it was his. A photograph of Rory and Amy on their wedding day caught his eye. You did well, son, he thought. He turned and tiptoed back upstairs.