Based on other reviews I ordered this in a size 4T for my 3 year old son. For reference, he's short at 32 pounds and 3 feet tall (37 inches to be exact) and the 4T suits him perfectly. It's not too tight and not too loose. I definitely recommend going up a full size.
LUCOWEE Anti Chafe Boys Swim Trunks: Boxer Brief Liner & UPF Quick Dry Technology
55 Review
π©³ Beautyin Toddler Boy's Swim Trunks: Printed Swim Shorts for Quick Dry Beachwear
46 Review
π Stay Safe in Style: Kanu Surf Boys' Protective Rashguard in Charcoal
44 Review
π Kanu Surf X Large Boys' Swim Rashguard Sleeve - Premium Protective Clothing for Swimming
43 Review
Funny Guy Mugs Tearaway Sweatpants: Playful Boys' Clothing for Fun and Active Days
49 Review
Boys' Adidas Active Sports Tricot Athletic Clothing
45 Review
π Boys' Outdoor Climbing Convertible Trousers - Waterproof | Clothing
47 Review
Arctix Youth Pants Reinforced: Large Boys' Clothing for Active Adventures
46 Review