I agree that having them come to therapy can help. My therapist all but forced me to bring my mom in to talk about suicidal ideation when I was very sick and she was not getting it. She didn't completely get it after that but at least she heard it from someone besides me and after I had an extremely bad episode about 14 months ago where she didn't know how to get me help she is much more on-board. It also helped my therapist to know what I was dealing with.