1. "My great-grandmother was married to my great-grandpa, who was an identical twin. She secretly started sleeping with his twin and got pregnant. To this day, no one knows who the real father is."
2. "My mother (who's still married to my dad) is sleeping with my ex-husband. Everyone knows except my dad."
3. "My grandpa had a highly successful furniture store in Pennsylvania. When he passed away, select family members were told he had a secret stash of gold and silver in his home. The stash mysteriously went missing and was never found."
4. "When my dad died, we found out that he was secretly married to another woman and was using a different name, all while still married to my mother."
5. "My cousin was in the military and got arrested for dealing drugs, so he spent 18 months in prison. His parents lied and told everyone he was actually stationed somewhere far away so no one would try to visit him. It's been a few years, but only a couple of us know the truth."
6. "A few years ago my uncle became a father and a grandfather on the same day. His long-lost daughter, who was kept secret from him by her mother, tracked him down and introduced both herself and her daughter to him."
7. "My cousin H. murdered his girlfriend in the late '60s and joined the military so he wouldn’t be found out. Also, his brother M. was poisoned by his wife while she was in prison for killing their three children."
8. "My grandmother's parents tried to pay off my grandpa the night before their wedding so that he'd leave her at the altar. Apparently they didn't think he was good enough for her."
9. "My mom recently told me that when she and my dad were first married, my grandpa (on my dad's side) tried to get her to sleep with him. She told my dad, but he didn’t believe her."
10. "My uncle is a pastor and cheated on his wife for years with a member of his congregation."
11. "My great-great-grandfather was sentenced to prison in the '20s after his mistress convinced him to murder her husband. No one in my family knew about it until I did some major digging on Ancestry.com."
12. "My aunt was a member of the Peoples Temple. She moved to Jonestown and drank the Kool-Aid, so she was one of the 900 people who died. My grandparents disowned her while she was in the cult."
13. "My great-great-grandmother's husband disappeared without a trace. Thirty years later, right after she died, they found leftover pieces of him that were chopped up in the outhouse. He had been abusive, so she took matters into her own hands."
14. "When my parents were dating, they broke up for a few days. During that time, my dad hooked up with some woman and never told my mom. It came out years later that this woman had actually gotten pregnant."
15. "My grandfather was a homicide detective in a big city, and he had a case in the early '60s that was so awful he literally didn’t speak for a month and was never quite the same after."
16. "My mom cheated on my dad with his nephew. They were both married, and at some point my mom even got pregnant. She unfortunately lost the baby, but I have a feeling it was my cousin's."
17. And, "My uncle secretly had TWO extra families. In one family, he had three daughters and an entire ranch with horses. In his second family, he had a toddler with a twentysomething-year-old, and they lived in an expensive condo downtown. The third family was with my aunt."
Do you have an even wilder, juicier family secret? Tell us yours in the comments below!
Note: Submissions have been edited for length and/or clarity.