Help!!! Daughters first birthday!

My baby girl is turning one. We are having her bday party May 18. We always throw pool parties and I have arranged our pool to be opened by then but the weather doesn’t look good. I have noooo idea how to throw a party without our pool! I need some ideas. What can I do at the party that would appeal to other kids from 1-6 years old... I have a small bounce house but if it rains we’ll all be inside. What the hell am I gonna do with a hunch of kids in the house. Can someone help me please?! how can I also make it fun for the adults. I’m stressing out.