CrocsGirl's Crocband II Clog (Toddler/Little Kid) Slate Grey 4-5 Toddler M

My son is size 4 us shoes, what size should I buy?

There is a Toddler 4 and a Little kid 4/5 but aren’t those the same? I am looking for big kid 4

what size should order son is 8years old wears a 2.5 us size what size croc shouls i order?

My godson is one years old. What size should I get ???