A/N: So this is pretty similar to another one shot of mine, "He'd Found Her Once." All of what happened with Andrew and Serena is the same: when he proposed to her, what she wanted to name their baby, how she died…this is just Andrew telling Mack the truth about his "mother."

Dear Old Mom

It was quiet that night. The other members of the expedition were talking softly amongst themselves. Mack sat across from Andrew, staring at his food. The elder Hartford was just about to ask his son what was wrong when Mack suddenly spoke up. "I remember having a mother."

This was the last thing on earth Andrew was expecting to hear from Mack's mouth. "Oh. Yeah. Well, I did want you to have a normal as possible childhood, son. Children do have mothers."

"I remember things like baking cookies and playing board games. The woman looked like me, and I think she was named Serena." He held his father's gaze unwaveringly. "So was she real, or did you make her up? I'd like the truth."

"She was real. I met her through Jessica."

Mack nodded. "OK. So if you loved her, where is she? What happened to her? Did she not feel the same way? Is that what you meant when you said you never found the right woman to settle down with?" There was a childlike quality in Mack's bright blue eyes – eagerness.

"It's kind of a long story, son. I'd rather not talk about it." Andrew lowered his gaze. "But it wasn't that she didn't feel the same way. She and I…well, we were very happy. I promise you that." He silently prayed that Mack would drop the painful subject. 'Let it go, please.'

"Dad, you promised me you'd tell me everything. I think my mother falls under the category of 'everything,'" Mack told his father. The tone of his voice let Andrew know that Mack wasn't going to let the subject of his "mother" go.

"She was my best friend. We talked about everything, kind of like you and Rose. We were so happy. Your mother…well, she was very creative and she could be stubborn when she wanted to be. She was charming; no one could resist her when she wanted something. I was head over heels for that woman." Andrew smiled, remembering. Mack nodded, wanting to know more.

"I asked her to marry me on her thirtieth birthday, and she said yes. She asked what had taken me so long. And then Serena told me that more than anything, she wanted children. I'd wanted a family just as badly, and I swear, Serena never looked happier. Later, we talked about baby names, and she told me one of our children had to be named Mackenzie."

"So that's where my name came from. I knew you wouldn't have given me such a girly name without a good reason." Mack grinned.

"Then, on our wedding day, she didn't show up. I got a call from a police officer telling me that Serena had been in an accident. She was dead at the scene. It was the worst news I'd ever gotten." Andrew squeezed his eyes shut.

"Car accident," Mack repeated slowly, remembering something from early childhood. "But that's how I remember her dying. I was four and we were in the car, and it was raining…I remember you finding me in the hospital and hugging me, telling me what had happened to my mommy…" Mack fell silent for a moment. Then, "I thought that might have been why you were so careful with me. Because you had almost lost me, too."

"That's what I intended for you to think. But there's more to the storey, Mack…The autopsy showed that Serena was pregnant. She had to have known; she was nearly three months along. I think she was going to tell me on our wedding night. It would have been her way of giving me a surprise."

"Mom did like surprises." Mack grinned, "I remember one Christmas…well, and I know it's not true, but I'm OK with that now. It makes more sense. I'm sorry you lost her the way you did. I don't know if I could take losing Ro – someone I loved in such a horrible way."

"You're stronger than you think." Andrew glanced at his watch. "I'm going to turn in. But you might want to remind your someone that you love her."

Mack grinned and got up. He hugged his father good night and went off to his own tent. Mack took his father's advice, and then found a small stack of photos he'd brought along. As his eyes fell on the last one, a smile crossed his face. "Night, Mom."