I cannot remember this stupid movie. It was a recent one in the last few years. two kids are dating and then find that their single parents get married. Now the two kids are brother and sister… HELP!!!
I cannot remember this stupid movie. It was a recent one in the last few years. two kids are dating and then find that their single parents get married. Now the two kids are brother and sister… HELP!!!
I doubt this is the movie you are thinking of but this was one of the alternate plotlines of Mr. Nobody.
that’s sort of the back plot of “Drive Me Crazy” though it’s not that recent.
https://en.wikipedia.org/wiki/Drive_Me_Crazy
Because I Said So (2007)?
Strangely enough, Melissa Joan Hart was in another one where this happened, a tv movie called Family Reunion: A Relative Nightmare back in 1995.