Cut small?

I'm not sure if Vans are cut small or maybe just this particular pair but I got an 11 for my 5 year old son who is an 11 in all of his other shoes that fit. These were small and very uncomfortable for him that I couldn't even let him wear them for his graduation pictures as intended. Also there weren't any tags on the shoe (I know Vans I have bought in the past have a skateboard tag on them) and no tissue paper in the box as if maybe they have been returned before but they were clean and looked unused. I plan on returning them but have been so busy. I hope it's not too late