My kid's in that age range, and all of the birthday partys we have visited have been pretty packed.

We're gearing up for the first "big" (i.e. not just the immediate family at home) birthday party next month and we're hoping it won't be a ghost town. She also doesn't usually like to be the center of attention, so I'm hoping the day of ends up going well. IDK we'll see how it goes in the future lol