Need ideas for daughter 7th birthday!!

chelsea

My daughter will be 7 in the beginning of December. We’re having a sleepover for about 8 girls at the hotel that has a indoor pool!! So what would be a good theme since it’s a hotel sleepover with a indoor pool? I was thinking about calling it a pajama party && letting them wear pajamas to the hotel, but then they would have to change in swimming clothes then back in pajamas. So what’s the perfect theme for this? Thanks in advance