I bought 3T for my son who now wears 2T clothes. It fit him like a small 3T, but the cuffs on the wrists were very tight. Maybe his arms are bigger than average, but I've never had another shirt that was so tight that his arms would go through the buttoned cuffs. I recommend only taking one size for this.
Star Wars, Marvel, and Disney Short-Sleeve T-Shirts for Boys from Amazon Essentials
50 Review
Van Heusen Sleeve Dress Poplin
42 Review
The Good Day Lab Clean Shield: Ultimate Comfort and Breathability in Tagless 4-Way Stretch Polo
43 Review
Boys 3D Graphic Hawaiian Aloha Short Sleeve Dress Shirt Tops with Button Down - Sizes 2-8 Years by Uideazone
47 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
👖 Boys' Outdoor Climbing Convertible Trousers - Waterproof | Clothing
47 Review
🍉 Fruit of the Loom 6 Pair Cushion Ankle Boys' Clothing: Comfy and Stylish Selection for Active Boys
57 Review