Ahoy there matey! For the wee landlubber in your life looking for long johns in size 6-7 years, here are a few top picks that will keep him cozy on cold days. Ergowear makes excellent quality kids thermal underwear known for their comfort and warmth. Their stretch jersey material with fleece inner allows full range of motion while trapped heat keeps chills away. Mums rave about how these hold up wash after wash and never fade or shrink. Check andbe sure to get ones with the reinforced gusset between the legs for extra durabilty where they need it most. With brands like Ergowear, you can't go wrong finding the perfect long johns to keep the little scallywag happy! Let me know if you need any other buccaneering boy's outfitting supplies - I'll be here to guide you port or starboard to the best booty!