i am a non practicing christian so i understand your friends concern and where she is coming from, but why not let her daughter have a different themed party, it doesnt even have to be on the same night, they could hold it ethrer the day before or day after. dont know the age of the girl but how about something like a karoke night, or some girly party with 2 -3 friends and have a sleepover, they could listen to music,do each others hair and make up, pl;ay twister and pig out on pizza, crisps/hotdogs, coke and stuff. i'm sure they could get lots of ideas on girly themes, enjoy.