My Horny Brother

I'm the eldest of 2 and was away attending university when my brother got our neighbor's daughter pregnant. He was 20 at the time and she was 18, but my horny brother was satisfied with getting the daughter pregnant he got the mother 38 pregnant as well. She a widow and on Christmas eve she had a bit much to drink, and my brother fucked her and her daughter. My brother doesn't drink, didn't indulge in drugs, drinking or smoking. We fixated on sex, and he took full advantage of his soon to be mother-in-law and her daughter the same night. I was only found out as I was sent to get him over for the family lunch. We live in the country and live fairly close together and rarely lock our doors. I expected to find my brother with the daughter not the mother as well and all totally naked. I didn't tell our parents of how I found him, but now she is pregnant like her daughter. I think they know what he has been up too, and he has confessed to me she still lets him fuck her. The wedding is soon, and he will be living with his mother-in-law after the wedding fulltime. But he is already doing that now anyway.