Well David Tennant's Doctor does refer to having children and being a father, He also refers to visiting Elizabeth the Virgin Queen and that the name is no longer suitable. so he seems getting some action somewhere.
There were quire a few kisses for DT's Doctor, but i think last's weeks episode with Amy Pond making a move is the closest they've shown to the Doctor getting it on.
I have watched Dr Who since it started with Wiliam Hartnell.
Although the Dr is presumed to have children,and there are inferred suggestions of sex,it has never actually been seen ,in any way shape or form,in any episode.
EDDIE51 recollection is of the Doctor's Granddaughter, not the Doctor's daughter, as mentioned by doomey! Obviously, if he has a granddaughter, he must have a son or daughter.