I got the size 18-24 months to fit our son who was 18 months at the time and has been wearing t-shirts/2 t-shirts for 24 months. It was a bit big but still fit well. The sleeves were a bit longer but I just rolled them up and it was great for the photos. Now that he's 22 months old, that's a good fit. The fabric is not as soft as hoped, but not too scratchy either. The material is thick and lasts a long time.
Star Wars, Marvel, and Disney Short-Sleeve T-Shirts for Boys from Amazon Essentials
50 Review
π Hanes Boys' Short Sleeve T-shirt Value Pack (3-pack) - Essential Wardrobe Basics
44 Review
Kid Nation Kids' Tagless Long Sleeve V π Neck T-Shirts 4-12 Years - 2 Packs and 3 Packs
45 Review
Boys 3D Graphic Hawaiian Aloha Short Sleeve Dress Shirt Tops with Button Down - Sizes 2-8 Years by Uideazone
47 Review
Arctix Youth Pants Reinforced: Large Boys' Clothing for Active Adventures
46 Review
π Boys' Outdoor Climbing Convertible Trousers - Waterproof | Clothing
47 Review
Boys' Adidas Active Sports Tricot Athletic Clothing
45 Review
π Fruit of the Loom 6 Pair Cushion Ankle Boys' Clothing: Comfy and Stylish Selection for Active Boys
57 Review