I disagree!! When my father was in the early stages of Parkinsons with dementia he went through a CRIPPLING depression. Luckily I got him diagnised early and got anti depressants and on dopamine ( which lack of dopamine is the problem with Parkinsons and alsi a HUGE factor in depression.)
My BIL in the UK has it. Horrible disease.
Still doesn’t mean his family, especially his kids, will carry what he did to them everyday till the day they die.