Warning: This post contains mentions of suicide, abuse, pregnancy loss, and drug use. A while back, we asked parents of the BuzzFeed Community to tell us the darkest secrets they've kept from their kids. They revealed the secrets they've never shared and why, and it's completely gut-wrenching. Here's what they had to say: 1. "I put my youngest son up for adoption when my kids were young (2 and 6). Neither of them has ever mentioned him. I have no clue what I would say if he ever showed up. I did not want him, but I was too far along in my pregnancy, so I chose adoption. I was young and selfish and not entirely sure he was my husband's (now ex), so I gave him up. I think about him often and hope that he has a good life." —51, Ohio 2. "My kids always ask me why their first cousin looks just like them. I have yet to find the courage to tell them that he is their sibling and not a cousin, as I had several one-night flings with my sister-in-law, resulting in her having MY child and not my brother's.…