Does every asd child have a highly sensitive person as a sibling?

[Mum0i754437]

Do any of you think HSP should be its own diagnosis or be a possible form of autism? I keep reading parents of asd kids refer to their NT child as HSP.
Has anyone else noticed or is this in my head. The NT child is first child so it cant be they are sensitive because they have an asd sibling.

There’s a higher likelihood of the siblings having ASD or another ND condition so I think sometimes (maybe often) it can be a case of the sibling having undiagnosed autism or another ND condition.