I don't know what show it was, wheather it was Outer Limits or not, but something along those lines. It was years ago, and the overall plot of the episode was that a woman goes back in time to kill HItler as a small child. He's not even a year old or so, and she ingratiates her way into the family household. Adolf's not a well child, he's weak and his family's all concerned that he won't live past it. Eventually her chance comes up and she takes off with the kid. I think her time trip was a one-way sendoff, so she decides to jump into a river while holding him to make sure nothing can go wrong. Well, another of the household nannys manages to observe all this. Earlier in the show there was a gypsy woman trying to find a new home for her son. (my memory's abit fuzzy on this, so if someone calls wants to me out for getting the details wrong feel free.) She then returns to that gypsy, takes her child and swaps a very healthy child in the now deceased sick one's shoes and the parents never caught on. Was a fun take on the Predestination Paradox angle of time travel.