I don't know if this will help.............My daughter who is now 7yrs old sucked her thumb also. She use to do it all the time when she was a toddler. The older she got she cut it down to when she was tired, or insecure. We tried everything we could think of to help her stop, but then decided that it's got to be a natural thing. What adult do you know that sucks there thumb, or carries around a blanket? We always gently reminded her to stop sucking her thumb when she did, but never made it a BIG issue with her. Eventually she stopped. (I think she was 6yrs). It was only when she was tired, we'd all laugh about it when we would say Laura? Stop sucking your thumb........your a BIG kindergardener now......then she would smile and pull her thumb out, and we'd all giggle. She did stop. Personally, I would'nt pressure your child. I think in time she will stop. I would defently make her concious of it though:)