NSFW - People of reddit who have had sex with an in-law or step sibling or parent, what happened? How did you get into that situation? and did anyone find out?

1. My brother and step sister had sex. They are both married and have children and there is nothing weird between them. The weird thing is that my dad and step mom encouraged it. They wanted them to be together and get married. My step mom will occasionally bring it up when she has been drinking like she still kind of wishes it had happened.
   — mintinthebox


2. I know someone who got pregnant from a guy and then later married him. No problems yet. Then, though, the girl's mom and the guy's dad got together and had their own kid. So now the original couple has a brother together - the baby has a sister and brother married to each other, but they were married before any of the weird shit happened.
   — kryppla


3. I went to high school with these 2 girls who had been best friends for most of their lives. In 11th grade one of the girls started sleeping with the other girls dad (older dad too, not a young dad- if that matters to you) and then began a relationship with him. Since she was 16 It was technically legal there. It was mortifying for the daughter because it was a small town and everyone knew. It tore the family and their friendship apart. It was awful to witness. I know it's not exactly what the OP asked for, but the question made me think of it
   — alyssa_wood






4. Briefly, during high school, my girlfriend's parents were on the rocks, the mom was sleeping with another guy, and the family was in rough shape. So the dad's response was to go after my single mom. Next thing ya know, my girlfriend's dad is having an affair with my mom, while the girlfriend's mom is having an affair with an old flame, they're going on double dates together and the girlfriend and I are suddenly unofficial step-siblings. And yes, it was awkward, even though it really had nothing to do with us. Thankfully, it didn't last long (maybe a month?). Her mom and dad reconciled and things went back to normal. There was one night they all came over to my mom's apartment with wine, we all drank, the mom and her fling went to a hotel, my mom and the dad went to bed, and then the girlfriend and I went to bed. That was weird. Does that count? Lol EDIT: RIP my inbox. Holy crap this blew up, lol. Trying to keep up with all the responses! Glad my most upvoted comment is just a hair short of a roll tide.
   — nburns1825


5. My dad had started dating following a messy divorce and, after being very coy about his activities for a few months, decided to introduce me to his girlfriend’s family. We all travelled to a relative’s country house and had a big party. The wine flowed pretty liberally. Eventually it was just me and the new girlfriend’s daughter who remained. We’d been getting on pretty well all night, and we were both quite drunk at this point. I stood, deciding I’d had enough fun for one night, and kissed her good night. One thing led to another, and we slept together. This kept up for a few months. I’m not sure if dad ever grasped why I was always so excited to visit his girlfriend’s place, but I was there in a flash if the invitation was offered. Fast forward six or seven years, and Dad married his partner. I was a groomsman. Now I like throw ‘I banged my sister’ in games of never have I ever. Don’t regret it at all. We were in our teens and we’re actually good friends now. Edit: Holy shit! This blew up. I know this all sounds a lot like the plot of a certain type of video found online, but I suppose miracles can still happen.
   — hatc


6. In high school one of my close friends lost her virginity to her mid 30s step brother and began a relationship with him. They didn’t grow up together. I always felt like he was a bit sleazy and that he groomed her (we were about 16). The thing is, they’re still together, 15 years later, with a kid and everything. It really tore their family apart for awhile though.
   — pubecube808






7. My great aunt married the boy next door at age 18 in 1945 or so. Turns out he was gay, and he wanted her to be his beard. Very unhappy. Her husband was estranged from his father who had already divorced his mom. So the Father in law joined the navy at the outbreak of the war and spent the war building airstrips all over the Pacific and Southeast Asia. He gets back from the War, meets his son's wife. He and my great/aunt have instant chemistry. They apparently start banging almost immediately. He's been off at war and she's in a sexless marriage. So lots of pent up sexual energy. Of course they get caught after a while. Mid act the son and ex wife show up. Actually provided a great out for the gay son, as he could divorce her, be the wronged party, and now be single with no questions about his sexuality. My Great-aunt suffered some social ostracism for this as it was juicy gossip for the city they lived in. However when the divorce came, she married her former father in law. They remained married until his death in the mid 90s (both his age and the year), after nearly 50 years together and three kids (plus grandkids). They were quite happy, but this story has always been one my mom kept from me until I was 30. Edit and TLDR: my great aunt cheated on her closeted gay first husband with his father. She ended up marrying her former father in law.
   — mobileoctobus


8. I did the deed with my mother in law once. It still makes me feel dirty when I think about it. I was separated from my wife at the time ( in the process of divorcing) and went to my mother in law’s house to help her with moving some furniture. We ended up sitting around after I helped and had a few cocktails and talked about my separation to her daughter. Fast forward to midnight and 6 drinks later and all of a sudden I’m looking at her with her jeans to her ankles and bent over the kitchen table. I swear to this day I really don’t know who made the first move or how it got to that point. It was crazy. The next day she calls me and plays the whole ‘I had so much to drink I don’t even remember last night’ card. I get it. I know it was her way of pretending like it never happened and I was perfectly okay with doing just that. I saw her numerous times after that and neither of us acted strange. We just erased it and acted like nothing ever happened. At the time I was about 30 and my mother in law was about 50. I’ve never told anyone until now. Edit: added 'until now'.
   — msk1974


9. Had a fling with my former sister in law up until recently. I split with my ex when she cheated on me back in 2011, and I effectively cut contact with that side of the family, SIL included. SIL was never on my bad side per se, but it was easier to cut her out and call it a day than try to surgically remove everyone else but her. She wasn't a model, but she wasn't bad looking either. Her and I got along well enough during my marriage because we married into the insanity. Fast forward to last year. Find out ex-SIL (I'm long divorced by this point) and ex-wifes brother separated because ex-BIL started fucking with someone behind her back (guess cheating ran in the family). I unblock her and reach out. I've been down this road and know how to handle the family in court, so I figure I'd lend assistance. Meet up with ex-SIL, help her do some errands (ex-BIL left nothing for her, not even a car), then head back and hang out. Started drinking, certain things came out about one another, and next thing I know we're in the bedroom going at it. We met up a few times until about a month ago. She found a guy that she wants to date so I stopped becoming her Plan B. No one has found out, and I'm pretty sure it'd be a shitshow if anyone did, hence the throwaway for the post. e: I’ve never gotten this many replies to a post before, so I’m slowly working my way through replying. I didn’t check this at all today, so forgive me for the late replies. e2: To clarify, my ex wife had a brother. His ex wife and I slept together after both divorces.
   — pm_ur_untrimmed_bush