For an Angel and Demon movie (Barbie and The Angel Princess) It thought of a way for it to be a family friendly movie. Barbie plays a daughter of a demon who goes to highschool, where everyone is mean of course, because they are all demon girls. She's very nice and sweet and gets bullied. Eventually she runs away and goes to an earth high-school. A character played by one of Barbie's friends (Brooklyn or Teresa maybe) is the angel princess. She's a lot like Tori from Princess and The Popstar. She's mischievous, rebellious, and loves pranks. She's a skater. In the angel High School, every girl is perfect, like a popular girl, and the Angel princess is expected to be perfect too, but her goofy behavior gets her ridiculed. She runs away too and meets Barbie the demon girl at the same human high school, they love each other and become great friends. Later, since the Angel Princess is missing, The King accuses the Demons of Kidnapping the Princess. There is going to be a war, that could destroy life on earth. The two girls team together and use their friendship to show that angels and demons can be friends. The two girls learn about responsibility, and those that used to be mean to the girls learn that differences can be good.
And, Dracularua in Monster High is still a family friendly vampire character, so Barbie could pull it off too.