I saw a baby with a floating thumb some time ago, and although he was only three years old, he felt he already knew what he was doing. The child was very cooperative during the consultation. When I said I wanted to see his hand, the child immediately took it out and asked some questions, which he answered very cooperatively, with very little need for additional information from the parents. The child’s hand was a typical type IV thumb hypoplasia, or floating thumb, which has no metacarpal bone and is attached to the palm of the hand by a skin tip, and the floating thumb was particularly small and did not match the other four normal fingers. Since the child was already three years old, he had developed the habit of using his middle finger and index finger to hold objects, which would have been much better if the surgery had been performed earlier. The parents had already taken the child to several hospitals before coming to me, and when the child was more than one year old, they learned about the surgical option of metatarsal reconstruction to preserve the fifth finger, which required removing the bone from the foot and moving it to the hand, and the parents were reluctant, thinking that the child already had problems with the hand, and that it would be too cruel for the child to remove the bone from the foot. However, as the child grew up and school was imminent, the family was anxious to take the child for metatarsal reconstruction if a better treatment plan was not found, and to get the surgery done before the child started school. Originally, the parents had already made an appointment for metatarsal reconstruction surgery, but they inadvertently learned about hemimelia reconstruction technology on the Internet, so they found me with the intention of giving it a try. After some understanding, the parents agreed with the surgical plan and felt that since the child had hand problems, it would be best to perform the surgery only on the hand and not to damage other parts of the body. The child was very quiet while listening to the surgical plan, and it was the parents who communicated with me. At the end of the talk, the child suddenly raised his hand in front of me and asked in a loud voice, “Doctor, will my finger grow?” “Of course it will!” A floating thumb is only missing the metacarpal bone or only the remains of the metacarpal bone, but there are still blood vessels and nerves inside, so it will grow even without surgery. But after surgery, the thumb will not only grow, but it will also have a better function and shape.