Found a baby bird under a tree?

It isnt really young, it can hop and such but it is out of its nest on the ground. It is under the tree its nest is in and it's parent keeps coming back and feeding it and sitting with it, but it is getting dark and my neighborhood has a lot of feral cats. I don't want to leave it out w/o protection but i dont want its parents to abandon it if i try and put it back