Godot is free and does 2d and 3d. I am not a game dev but there are a heap of YouTube/web based tutorials, free models and everything out there for you to get

Godot is free and does 2d and 3d. I am not a game dev but there are a heap of YouTube/web based tutorials, free models and everything out there for you to get started with!!!!! Good luck and enjoy the time with your kid