We recently (after a lot Of speculation) found out my dad and eldest sister are In a sexual relationship. They aren’t blood related, but he adopted her when she was 4, after meeting my mum as a single parent when she was 2. He’s been the only dad she’s ever known, she has his last name like all of us, she was never treated any different, she’s always called him dad and for the most part we all pretty much forgot he wasn’t her biological dad. He and my mum split up 5 years ago, she moved out and remarried. My sister now 35 moved home to live with my dad a year or so after, which was kinda strange. But it was the home we all grew up in, so we are all comfortable there. all other siblings had already left home and married etc, following her moving in…. We noticed they were spending a lot of time together. Lots of little camping holidays, and air b&b bookings. A few months ago whilst visiting we noticed her bed was stripped and unslept in, I then checked this the following visits and it was never made up. Last week they told the family they are together, she’s started calling him by his actual name instead of dad, and they say they are doing no wrong as they aren’t related biologically, and that they are in love? I feel absolutely heartbroken and sickened and think they are and will be making the biggest mistakes of their lives.
My sisters in a relationship with my dad?
