The study doesn’t provide answers as to why parents mental health issues improve when the kids get treatment, but I think this makes a lot of sense:
“Relationships are reciprocal,” says Laura Mufson, the associate director of the Division of Child & Adolescent Psychiatry at Columbia University, who was not involved in the study. “If one child isn’t doing well, if they’re having mood problems, if they’re more irritable—it’s affecting their behavior that impacts the rest of the people in the family.”
An over abundance of stress is a known risk factor for mental health issues. Having a child, or anyone in your immediately family, with an untreated mental health issue would be incredibly stressful. Having that person in a situation to get help, and start to get better would ease that stress, thus creating an atmosphere that is more conducive to improvement in their own condition.
This also provides further evidence, unfortunately, that being close to someone dealing with depression or other issues, is draining. That’s not to say we shouldn’t be there and care for them, but it does show us how imperative it is that you also take care of ourselves.