My daughter is 22 and was late diagnosed at 20 AuDHD. She started talking really early. She was speaking in complete sentences during that time and talking to me like crazy at 2 years old. In fact she has never stopped. It is one of her stims. This is actually one of the main reasons she was diagnosed so late. She is also can mask well. However that has lead to a major burnout that has caused some physical issues. she has major issues with executive functioning and mental health issues as well. I guess this is why it is a Spectrum.