5 year old girl with hyper and anxiety issues

Hello
I have a 5 year old girl who loves to eat sugar. She is very hyper very loud very active. She loves eating sugar out of sugar pots and loves any kind of sweet. After sugar consumption she gets extra hyper. Her mother tries not to give her sugar but she someone gets to sugar and eats it even out of sugar pots. She's very slim her diet is poor and picky. She has to be fed because If she uses her own hands to eat, she says her hands will get dirty and she gets upset. When she goes to school she doesn't eat her lunch so her hands don't get messy. The environment she lives in is not healthy. It's very aggressive, loud and she has seen her parents fight a lot since a baby.
She talks loud and plays loud but if someone else is loud she gets really upset. She keeps her fingers in her ears because she doesn't like noise.
As a baby she has alway has crying spells. She cried a lot for no reason. Her parents handled her crying in a poor manner. As she grew into a toddler she didn't like going to gatherings she would sit in the car and not go inside anyone's house and would just watch iPad. If there's a gathering at her place she would stay in her room and not be part of the party. She would only be herself with one someone who she's really comfortable with but still would keep her fingers on her ears.
She had has hearing tests done its normal. She has seen doctors and they have said its maybe anxiety but her parents haven't seeked out any psychological help. She has gone much better over time but still keeps fingers in her ears when anyone outside her own family is around. She is a very active kid talks loud and hyper.
Her mother is really concerned and has had tough time living with her in laws and abusive relationship.
since I have had such good response on this forum with my own two kids problems I would love to help out a friend in need.
What would help her calm her kids down? She also sleeps odd times at night.
She is a creative child with wonderful imagination. She loves to color and write whatever she can. She learned to talk by 2 walking by 14 months crawling at 10 months. All her milestones were on time. She's average height skinny built big eyes.
If you need more info please let me know
Thanks