The fabric is soft but will shrink after washing and drying. I read about it so I took these photos to see how much they are shrinking. Beige was the one that ran smaller (almost 4cm / 1.5in) and I ordered a size 7-8 so you could probably order a size up to get the right fit you want or want.
π Hanes Boys' Short Sleeve T-shirt Value Pack (3-pack) - Essential Wardrobe Basics
44 Review
The Good Day Lab Clean Shield: Ultimate Comfort and Breathability in Tagless 4-Way Stretch Polo
43 Review
Boys' Long-Sleeve Disney Star Wars Marvel T-Shirts by Spotted Zebra
46 Review
Soft Brushed Fleece Crewneck Sweatshirt for π Boys and Girls 4-12 Years - Kid Nation Kids
42 Review
Funny Guy Mugs Tearaway Sweatpants: Playful Boys' Clothing for Fun and Active Days
49 Review
π Fruit of the Loom 6 Pair Cushion Ankle Boys' Clothing: Comfy and Stylish Selection for Active Boys
57 Review
Boys' Adidas Active Sports Tricot Athletic Clothing
45 Review
π Boys' Outdoor Climbing Convertible Trousers - Waterproof | Clothing
47 Review