I disagree with letting your kids know anything. I don't know what good can come from that.
My daughter's therapist told me not to tell my daughter about my PTSD, nor about how my mother was bipolar and she took her own life. My daughter is a teenager, and I found out I had PTSD when she was about 10 after I witnessed my mother's death, but also was dealing with an abusive relationship with my daughter's father. She doesn't know I have PTSD, and I will not be telling her, maybe when she's an adult. My ex husband, unfortunately, told her all about my mother, whom I never let around my daughter in the first place when she was alive.
I grew up with a mentally ill mother, and it was covered up for the most part to the outside world, but it was always the excuse when my mother did something violent and crazy. I hated her for that. I was constantly stressed out to the point of being 6 years old and pulling my hair out in clumps, but she had bipolar disorder, so it was ok for her to act like that. That was the message I got.
I will not let my daughter grow up with any worries about my health or mental state. I keep my panic attacks hidden from her. I keep my anxiety from her. I keep my physical health problems hidden from her. I absolutely dread having to be social or be around people that I don't know, I have to suck it up many times, and have learned to fake normal. Even when I'm having a panic attack. It's the same idea as not involving kids in finances. They are innocent, it shouldn't be their job to worry about their parents' problems. She already has one parent that is a drug addict and a violent man, I need to be the complete polar opposite of that. Kids need strong roots to be able to survive out in the real world.