I have read a lot about those disorders, and it is thought that it is possible both of those disorders can be passed on genetically. It doesn't mean it's definite, but it's possible. My ex boyfriend had two little brothers under the age of four that took medicine for ADHD, so I wouldn't call kindergarden too early. But I don't know. And my cousin's son I believe from the start has been ADHD, and she has it, so he gets it from her I'm sure. My sister got it from her dad.
I have Borderline Personality Disorder, or so I've been told. Who knows, I'm one of those people that thinks it's ridiculous to dwell over something that's in my head too, but it does scare me sometimes. I have also dealt with a lot of depression, and Eli's dad has gone through a lot of depression as well, and I've heard that can be genetic too, so I'm definitely worried about Eli. I know that depression and even BPD can be influenced greatly by the environment you are raised in though (maybe even bipolar, you never know) so I'm hoping if I raise Eli right, and in a good environment and whatnot, that we can avoid it. Who knows. All I can do is try.
But I feel your pain, and it does scare me. I know with BPD I wasn't an easy kid for my mom.