It's different with old gods when they look like a child. It means they reincarnated recently.

Though maybe there are some old gods that look like kids? I mean, there was a cat, so why not a kid? I've seen pictures of Ebisu as an adult though.

[Amaterasu on the other hand...]

But with our generation, there's Nanako and Elfnein as gods? I can't think of other kid gods though there are a lot of people I haven't met. Lots of shinki though.