I have a pack of socks for the 4-7 age group. Took 3 pairs for my two girls for a ski trip. I figured they could both fit in this size range as I have a 3 year old who wears a 6.5c/7c shoes. And a 6 year old wearing size 2.5/3 year old shoes. Perfect for 3 years! Closes the shin area and does not stray on the toe or heel. For a 6 year old they fit but I would love her feet in size 8-12 socks. BUT it still works for our purpose. There is no need to buy two different packs if you are happy with the slightly shorter socks. I haven't driven to their destination yet to test how warm they are in cold weather. But inside they feel incredible. They look small when they come out of the box but they stretch quite well (as you can see in the photos). Hopefully they don't slide down too much. Can return to check updates as soon as we use them.