Happily Married

I'm Jake 38 short for Jacob and I've been married 10 years and have 3 children, another 2 on the way. My wife now 35 and pregnant again and is due in September. She has an older sister 38 and her sister got divorced and didn't have children, the reason the divorce her husband didn't want children and she did, and she married at 34. So, with her wanting children and him not led to the divorce, he 39 claimed he wanted to pursue his career and children would hinder it. She counter claimed he hadn't told her he didn't children and therefore lied to her by not saying so and he only wanted a wife to help with his career something else he hadn't said to her. With the divorce granted and her winning big, she then got very depressed. Not because of the divorce, but that she might never be a mother and have children of her own. So, depressed was she my wife decided to help her sister and first had her sister sell up and buy the house next door to us. Not saying anything to me, I just thought her sister wanted to be closer to her family. Only after she was moved in and settled did my wife asked me to get her sister pregnant. Of course, I was very excited, no I was totally shocked and couldn't answer. But after getting over the shock, I asked why me and was told I was the only one they could use stating I had no brothers, and their brother would make it incest. My puzzled look was answered by, we want to keep it in the family and that I didn't have an answer too and after some thought decided to agree on the condition that it was an all-in arrangement as straight sex was their preferred course of insemination. Meaning a threesome and they quickly agreed, and threesomes is the way my sex life is now. My wife got pregnant first, but her sister quickly followed and that's how I got to be waiting for 2 children to be born from 2 sisters. But the secret isn't restricted to me, my wife and her sister, their mother and my mother both know nobody else is in the loop. Neither my father, their father, my sister or their brother knows of our arrangement. I thought once the baby was born my sister-in-law would be happy and contented. But I've just learnt from my mother that at least another child is being thought about and asked who told her that and it was my wife's idea. I asked my wife and she said she liked the threesomes we were having and wanted to continue having them. I must say I like the threesomes too.