I typed the sentence "Are these your children?" and got the question wrong. Since "rūs" can mean either baby or child, my answer should have been correct.
Rūs can mean baby or infant, I don't believe it can mean child.
Interesting. I thought I remembered it being defined somewhere as baby or child. I'll have to check the wiki when I can get into it; it seems to be down right now.
So on the wiki it says it means "baby, child"