One child, born in winter, wore these for 2-3 months. They open in the front, making them easy to put on. Uniqlo underwear is durable and can be used for a long time, but I'm selling them because I don't plan to pass them on. The two gray and white ones in the upper left are from Akachan Honpo, and the other three are from Uniqlo. The combination underwear has the tags cut off. The collar of the white long-sleeved underwear seems slightly yellowed, but overall, there doesn't seem to be any noticeable stains. Please understand that these are used items. Thank you.