I had a niece (deceased now) who was married and had two children (girl and boy). When the boy was in his teens, he got into drugs. My niece and her husband owned quite a lot of property and were considered, "well to do." But, in less than 10 years or so, that son had taken his parents for just about everything they ever had (threatened suicide, drug lords were after him...or so he said...and he need XXXX thousands of dollars or they were going to kill him, etc. They paid his rent, provided for support for his one son. It was heartbreaking to look back on. She died at a fairly young age. But, they lost everything to their son's drug habit and even ended up living with their own parents.
Depending on one's ability to administer, "tough love," a grown child can absolutely bankrupt their parents. I watched it happen from a distance.
I don't know how involved they got into their son, MD's personal horrors. But, I do know it can absolutely wipe out an entire family (even generation) unless they use TOUGH LOVE.