My daughter has definitely been impacted by my illness and especially the combo of BP, C-PTSD but she is a mature well balanced woman in a long term healthy relationship with one son and another baby on the way. I insisted on therapy so she could deal with my illness. She went though a period of hate and blame as a teenager but we got though it. The early therapy also helped her with her own struggles with her BP. She's much more stable than I ever was. A lot of the credit goes to my mum for being there for her. My mum went to education classes for relatives of those with mental illness along with my aunt. I have cousins with BP too. So although my father's side of the family doesn't acknowledge MI my mums does and it has helped all of us.
In my view the best things for kids is honest dialogue with emphasis on it NOT being their fault.