A little big.
My son is 1 year old and usually wears clothes for 12 months. I ordered 9 months and it fit great and still had some room to grow.
π Boys' Outdoor Climbing Convertible Trousers - Waterproof | Clothing
47 Review
π Fruit of the Loom 6 Pair Cushion Ankle Boys' Clothing: Comfy and Stylish Selection for Active Boys
57 Review
Waterproof Cozy-Dry Rain/Snow Pants for π§ Kids by JAN & JUL, with Fleece Lining
64 Review
Boys' Adidas Active Sports Tricot Athletic Clothing
45 Review