Aaron wondered what, exactly, he was doing standing on the front porch of the Rossi mansion, a guitar case in his hand. Or rather, he did know, but he still was uncertain about giving lessons to the newest Mrs. Rossi. After all, she had made it quite clear when she had left the BAU that she wouldn't be looking back or focusing on the past. That had included cutting all contact with the team the moment the Director had chosen her replacement.

Exhaling forcefully, he pushed to doorbell and waited for the door to open. "Isabella, Katarina, stop it!" he heard from behind the door and smiled, picturing the toddler twins giving their mother problems. The few times he had been invited over for supper had been a revelation, showing him a totally different side of her. "David, will you please get the children?"

As Aaron listened, another, heavier, set of footsteps came near the door, and from the delighted squeals, he knew that his colleague had indeed come for the children. "I'll have Bernice look after them while your little lesson is going on."

He winced a little at the tone his friend took, and felt his brow furrow, as the pieces of a badly damaged marriage fit into place. Clearing his throat, he hoped that everything would fine as he taught Erin how to play the guitar. He really didn't want to get involved in the middle of his best friend's latest disaster of a marriage. He'd already been through that once before.

Just then, Erin wrenched the door open, and he tried to look anywhere but at her tearstained cheeks. "Hello, Aaron. You're right on time. David's decided that our lessons are going to be held in the living room. He'll be able to hear us somewhat, since he'll be in the den, playing poker with his friends."

Her voice was sadder than he had remembered it to be, and for some reason that made him want to reach out and hug her tightly to him. "That's fine with me. This first lesson will just be the basics, anyway. I doubt he'll find much of interest in listening to you play chords over and over again as I teach you the correct fingerings."

Erin nodded and beckoned him inside. He followed after, taking in the feminine touches that Erin had added to his friend's house in the three years they had been together. Once they were closed in the living room, he took the time to really look at her as she pulled out her guitar, awkwardly fumbling it onto her lap as she sighed. She had lost weight, and it seemed like she was wasting away.

"Aaron, come, join me on the sofa. I promise, I won't bite." There was no mirth behind her joke, even though she was smiling at him, and he nodded before closing the distance between them and taking a seat. Pulling out his guitar, he quickly tuned it before setting it aside and reaching out for hers. She handed it over and he smiled to see the quality instrument that she had bought for herself.

"This is a gorgeous instrument, Erin."

"Only the best for David's wife," she muttered, looking down at the carpet. It bothered him to hear her address herself so, and this time he reached out, resting his hand on her shoulder. She shuddered a little, and he wondered how long it had been since she had felt a kind touch. The living room door swung open and she swallowed a gasp as her head shot over to see who it was. Aaron looked himself and saw a beautiful little girl standing in the doorway. "Isabella, you know that this is Mommy's private time. Where's Bernice?"

"With Katie. I want to hear you play, Mommy." Her lower lip pouted out, but Erin shook her head. Ignoring her mother, the toddler ran over to them and clambered up onto the sofa, wiggling between Aaron and her mother. "Are you Mister Hotch?"

He gave her a tender smile as he nodded. "I am, Isabella. You look very nice today."

"Thank you. Mommy made me this dress. Katie has a matching one. Are you going to make our mommy happy?"

Erin met his eyes over her daughter's head, and he saw the shock and panic written there. He let his smile linger as he nodded. "I am going to try my best, honey. But, I think that you should listen to your mommy. We grownups need to have some privacy while I teach your mommy how to play."

The little girl nodded before slipping off the couch and running back over to the door, just as an older woman, whom he assumed to be Bernice, appeared. "I'm sorry, Miss Erin, she got away from me before I noticed."

"That's fine, Bernice. We haven't really started yet. I'll be up to relieve you when this is over."

"Oh, no, don't worry about that. You need your rest. Take your time."

Aaron filed away that piece of information and waved to the toddler before Bernice picked her up and closed the door, leaving them alone once more. Turning to face Erin, he found that she was crying softly, and he had no idea how to comfort her or if he even should. "I've had a really long recovery from the pregnancy. It was something that I wanted to do for David, but I had no idea it would take this much out of me."

"From the little Dave told us, you were such a trooper throughout the pregnancy." What he didn't say was that as soon as the twins were born, Erin had become an afterthought to him, only being mentioned when Penelope asked after her.

She smiled at him, a soft look of hope on her face. "Really? He talked about me?"

Aaron found that he couldn't break her heart in that moment, since he knew that she was obviously fragile in that moment. "He did, he does. You are always his beautiful, loving, wife." His heart ached at the small lie he told, but he knew that it was that or destroy hope in her.

"I'm glad to hear that." Erin looked down at her guitar, dragging her fingers down the strings. "Well, I guess we should get started before I waste any more of your time, Aaron. I know that you'd much rather be home with Jack. I know that you're only doing this because David asked you to."

Those last words were so forlorn that he couldn't keep from leaning forward and pulling her into a soft hug. She was stiff, resistive, to the embrace, but he still held her, knowing that sometimes it was the actions that got through to the heart. Finally, she relaxed a little, laying her head on his shoulder and bursting into sobs. "I have you, Erin. You're not alone."

He realized that his words echoed the ones he had spoken to her years ago, when he thought they were losing her, and she must have realized the same, as she cried harder, letting him stroke her back. "I'm sorry, Aaron. I just feel so lonely."

"Don't be sorry for your feelings, Erin. Come, let me teach you how to play."

She nodded and sat up, lifting her shirt to wipe her face clean of her tears. Aaron found his eyes drawn to the pale skin of her stomach. "Would you play something for me first? So that I can gather my emotions?"

He found that he couldn't deny her request, so he nodded and picked up his guitar, strumming a few chords. "Is there something in particular that you want to hear?" he asked.

"Do you know the song, 'The Water is Wide'?" He nodded. "Play that for me." He began to play the folk song, and was surprised to hear her sweet mezzo-soprano fill in with the lyrics. "The water is wide, I cannot swim o'er. And neither I have wings to fly. Build me a boat, that can carry two. And both shall row, my love and I."

Aaron found himself following her lead, wondering how many verses of the song she knew, listening to her sing about the heartache of love. "I can see now why you want to learn how to play. You need something to accompany that voice of yours."

She blushed as she nodded. "Yes, and I want to learn that song first. It's one of the ones that I learned at my mother's knee, back when I was young. I took more easily to the piano, but the guitar will be nice to learn, too."

He nodded and set his guitar aside before getting up. She blanched, and he smiled at her, trying to get her to relax. "I'm not going anywhere, Erin. I just need to sit behind you so that I can position your fingers on the right strings. After you get the basic chords down, I'll go back and watch you play."

"Okay," she breathed out, her spine becoming impossibly straight as he settled in behind her. He tried to ease her nerves, to touch her in an appropriate manner. "So, what do I do first?"

"Your right hand goes here," he said, positioning it on the neck of the guitar. "And your left hand hold the pick to strum over the strings. Here, let me show you the position for a C Major chord."

His fingers closed around hers, and he breathed in the intoxicating scent of her perfume as he began to show her how to play. A small voice in the back of his head told him that maybe he shouldn't have been so willing to agree to this, as his feelings were quickly growing confused and knotty. Still, he would soldier on for Erin's sake. God knew she needed a friend, and he was determined to be that for her.