SPD does run in families. Your difficulties dealing with a more hyposensitive type child if you are a hypersensitive type adult, could be quite a lot.

This weekend, my sister-in-law, my two nieces, and nephew visited me. None are genetically related, but one of the nieces is hypersensitive with either mild Autism or a strong case of Aspergers.

My sister-in-law goes into rages at the least amount of "normal children sounds" coming from her children. I actually had a harder time dealing with my supposedly normal sister-in-law's rages than I did my niece who sang the same annoying song almost continuously while spinning/dancing whenever you didn't require her attention. My nephew was a typical 5 year old boy slime and noise bot. The oldest and "normal" niece by herself was fine sensory wise to me, but when her sister was getting my attention she would go out of her way to be a pain in the butt. The oldest niece (10 years old) was the most common target for her mother's rages.

Anyways, the three kids burned away my sensory resources, but with breaks I was able to survive them. Their mother spending ten minutes with them with me in the room and I became a frazzled mess. I was doing most of the childcare this weekend by myself, although my husband took over when I needed breaks.

I love these kids, but my sister in law right now... not so much. Because I am hypersensitive, each time my sister-in-law yelled at her kids I felt like I was the one being personally attacked. Some of her rages felt even like fist blows to my body. The kids became hysterical or shut down (my Autistic spectrum niece) after she visited with them. Then she would complain about all their behavior problems, when for the most part before she showed up they were semi-good kids.

I don't know how to talk to my sister-in-law about her verbal abuse of her children. My husband said that his mother was the same way with my sister-in-law when she was a child.