There is a Disney movie made like in the 90's I think and (I don't remember if it is a Disney movie or not lol) But this lady is about to marry his father and it turns out she is like a monster or something like that. And when everything ends the dad and the son go to a cave somewhere and behind some kind of cloth is the mom and daughter. I can't remember what the name of this movie is!

Anyone who can tell me what this movie is I would be eternally grateful!

http://dreamers.com/indices/imagenes/peliculas.7174.IMAGEN1.jpg
Step monster(1993)

There is a Disney movie made like in the 90's I think and (I don't remember if it is a Disney movie or not lol) But this lady is about to marry his father and it turns out she is like a monster or something like that. And when everything ends the dad and the son go to a cave somewhere and behind some kind of cloth is the mom and daughter. I can't remember what the name of this movie is!

Anyone who can tell me what this movie is I would be eternally greatful!
OMG! Thank You SSSSSSSOOOOOOOOOOOOO MUCH! I have been looking for it for live over a year! Lol THANK YOU!