"When would be about six months ago. As for the how... do you really need me to spell that out?" Jack asked. He smirked at the Doctor and playfully poked Gwen back. The two of them kept at it for a few more minutes before she grinned and gave him a shove.
"But yes... I'm the dad. And no, it wasn't just a quick fling or anything," he quickly added before the Doctor could jump to any comclusions. "Martha and I have been together for quite a while now. So don't go getting the wrong idea!"