1)Doctor: Tentoo. As he watched Rose helping their little boy carefully ice the gingerbread TARDIS, he felt the urge to wrap them in bubble wrap to keep them safe from the world.
His single human heart was filled almost to bursting with love for his family. A life on the slow path, with a marriage and children was something that he had never even wanted before he met her. His Ninth self-had grumbled and whinged whenever he had been forced into visiting Rose's mum even though he secretly didn't mind. His Tenth self-had enjoyed the domestic side with Rose and her family. He had even come to think of Jackie as his family. That had made the pain of separation that much greater.
This life was a gift, not just to Rose but to him as well. And the thought of losing it, of something happening to Rose or their son… It was something that he couldn't let happen.
"Daddy," Jamie called to him. "Come help."
Crossing the room, the Doctor picked his son up. The little boy giggled as he dad blew a raspberry on his stomach before placing him back in the chair. He smiled at his family and wrapped his arms around Rose's waist. The gentle swell of her stomach was the only outward sign that in a few months, their family would grow by one, possibly two. He was still convinced that they were having twins, having already felt the flutter of more than one new consciousness in his mind.
Either way, he loved this life, loved his family and would do everything in his power to keep them safe. Hopefully the Universe would be kind and he's never have to test how far he'd go.