Brasil Logo Ii unisex-child Baby Flip-Flop Sandals

My boy is a size 2.5 in little kid shoes, so I am wondering which sandal size I need to get him? He is 10 years old.

Is havainas “little kid” sizing the same as youth in other brands? i’m trying to order for my 10 yr old son.

I want to buy these but the reviews are split as to them running big or small. Which is it??

Do the toddler sizes have back straps? my son is a 9 toddler now, based on reviews i would size up to a 10. thanks!