"TARDIS stands for Time And Relative Dimensions In Space," she explained, glancing over at Jack (who nodded in confirmation). "It's a space ship and a time machine. So it just sort of materializes and dematerializes where it needs to go."
"And there's no kid. You know how we usually referred to planes and ships as a female? It's the same with the TARDIS, except she's sentient. So yeah... she actually has feelings about people. And once she came to terms with my new condition, we've been fine ever since," Jack explained.
He looked over to Martha and nodded in agreement. "You're right though. It's our life and the Doctor is just going to have to accept it. He knows we're here for him when he needs us, but we both chose to leave. I chose to come back here to Torchwood, and you chose to leave for your reasons. Either way, he needs to get over his attitude about us and your being pregnant."