My child wears small children's shoes, size 12, and the average (8.5-2) fits just right. I suspect they get uncomfortable as his foot gets a little larger, so I recommend going up a size if you're approaching the upper sizing range. Quality socks with smooth seams that hold up well after the first wash.
12-Pack of Jefferies Seamless Sport Socks for Boys
45 Review
Aminson Grip Ankle Socks: Non-Skid Slipper Crew Socks for Kids Boys and Girls - 6/12 Pairs
49 Review
π Aminson Active Ankle Athletic Apparel for Girls and Boys
48 Review
Jefferies Socks Boys Seamless Toe Crew Athletic Socks 6-pack
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
π₯ Stay Warm and Active with Rocky Fleece Thermal Underwear Bottoms for Boys
44 Review
Boys' Adidas Active Sports Tricot Athletic Clothing
45 Review