I recently kept a 4-year-old special needs little boy. He did not talk and he was not potty trained. His only form of communication was to point to what he wanted. I learned and taught him basic sign language. It bought me so much joy when he started using sign language. He learned sign language for potty and I am proud to day he is potty trained now. He was doing sign language with his parents and they had to call me and ask me what it meant.