Question: fun things to do with siblings on a rainy day?
Answer: Lava game. It's fun active game for at least 2 players/siblings. ... 
T-shirt walk. Put both kids in one t-shirt and let them walk in the house. ... 
Pillow sumo. ... 
Apple roll. ... 
Twister game is a classic, but perfect to play on a family night or on a rainy afternoon.
The ball roll. ... 
Freeze game. ... 
Catchy Catch.