My son wore these brand new ones to his daycare for a day and they are already pilling quite a bit.
I'm not sure how well they will hold up over time. The small size suits him (he is 3.5 years old and weighs 31 pounds).
Warm and Soft Wool Socks for Kids - Cute Animal Design, Thick Thermal Crew Socks for Children and Toddlers in Winter
43 Review
Children Toddler Thermal Cotton Winter Girls' Clothing
58 Review
Amazon Essentials Little 3 Pack Shimmer Girls' Clothing in Socks & Tights
63 Review
TeeHee Pairs Various Valuable Kids Girls' Clothing
56 Review