What’s the smallest size kids skates to rent?

Baby 6 through men's 14 according to their FAQ

I have no idea. But i am sure they'll find something that works. But if kid is too small, i wouldn't put my kid on the ice where people are skating for the first time or second time in their lifetime. It's like being on the highway with cars around you, none of them can drive, their first time sitting behind the wheel.