My seven year old daughter constantly sucks her thumb - especially when tired - if we're lucky, this is accompanied by chronic nose picking. I can get her to stop the nose picking sometimes but the thumb sucking seems to be something she needs. When she did try really hard to stop, she replaced it with pulling her hair out. I decided the thumb sucking was preferable. Do I just let her do it until she decides to stop. I remember my sister constantly being told to stop and she eventually gave up age 13.