Jenny didn't waste any time pulling him into what used to be the master bedroom and diving into him on the bed. He was her, but he wasn't as tight as he'd been at first, and soon two little girls were screaming in ecstasy as she thrust in and out. She exploded, and he was still pumping his hips up and down on her, getting closer and closer, and finally collapsed on top of her. Now would be a good time to tell her, while they were both exhausted.
"I'm pregnant, Jenny." He grinned at her, and she just stared at him, slack-jawed. She squealed in delight as her brain seemed to process it, and wrapped her arms around her new twin tightly, hugging him and beginning to cry. "I'm gonna be a daddy twice! This is so cool, little sis!"
He held her on the bed, reveling in the feeling of being filled, an old sensation but new in this body. Carrying a baby to term in a little girl's body would be strange, but no stranger than being the twin of a little girl with a grown man's genitals, the new sister of a ten-year-old boy-turned-pregnant-woman, and the new daughter of a woman with a little boy's genitals.
Bill couldn't have been happier.