Chaos247

Hello. I am fairly new to Healthboards and usually I am on diabetes or thyroid but have been reading the support here and it looks great so I have a few questions.
My nephew is Autistic. My sister in law claims he is high functioning and I had my doubts. Maybe I do not understand high functioning but I would guess it to be alot better than he is. He will be 5 in November and is a very large child. He weighs 68 lbs. He was 11 when born. He spoke a few words until 18 months old then stopped. He also did not walk until 18 months old. The spinning items and flapping hands started earlier on. He still continues all this behavior and has added new ones since.
He is in a early education program. He does not speak at all. He can feed himself by hand but does not eat sweets. He eats walking around or on his back with his head tilted upside down. It worries me he will choke. He is very much into junk food such as potato chips. (Has only recently ate mashed potatoes). He is very limited on what he eats. Mostly meat and chips. He recently ate applesauce for his teacher at school but will not for his Mom and Dad at home. I guess I am asking how much of this is autism and how much could be helped (such as being a stubborn child which he does exibit signs of this but is easy to confuse the two.) He will not eat with silverware. He does wear clothes to school but will not at home. He is not potty trained and seems to not be interested at all. He even plays in his feces. He does not feel comfortable with other folks around and does not interact except with his mother and that is more like she is his servant instead of a mother son relationship. He knows he can depend on her. Does not interact with father at all. On a good day if he gets close enough and is in a good mood you can "tickle him" and he will giggle. This is mostly with family only. When his teacher changed at school it sent him into a tizzy,,bless his heart he hates change and I know that is part of it. He has several routines. He will spin items incessantly and loves to play with all the silverware in a metal bowl yet does not like loud noises from someone else. He loves to play in the water whether a bath or the water hose. He does laugh but only to himself when nothing funny is happening. This is only a short list of things he does I am sure I am leaving alot out but would this be high functioning? My husband and I do not think so. He has made very few strides in improvement and has been diagnosed since 3. Any advice would be appreciated. My sister in law is a very good mother and reads everything. I would love to be able to help her more. She never complains and has so much love and patience for this child. I would love to be able to watch him so she could get away but at this point would be impossible. She is aware of gluten free diet and vitamins but how do you get a child that cannot understand he cannot eat what he wants or one that is unable/will not swallow pills. He does take a Flinstone vitamin but she has to crush that and hide it in his juice. He will not drink milk.
Sorry this was so long. Thank you in advance for listening.