Is it common? That depends on your context. Since your particular context includes an internet connection, literacy, and living in a situation with the means to reserve space for a child that isn’t home full-time, I feel pretty confident in my estimation that it’s probably not common.

Is it harmful? No. Honestly, I think it’s pretty sweet. My only advice is to not let it stray into forbidden territory, but you seem to already have a pretty good grasp of where the line is.