Special Family

While at university I met my now wife and we were getting very well and started having sex and I was thinking of asking her to marry me. But she got pregnant before I asked, I already had a ring and was waiting for the second anniversary of us meeting. Which was a week away to ask her, when she told me she was pregnant and so I asked her straight away. She said I didn't have to marry her just because she was pregnant, I told I already had the ring and took her back to my place and offered it to her. She accepted and we married the next month, I was just about to graduate, and she had another year to go. So, we stayed near the university until she graduated and then moved to be closer to her family with son. I got a great job, and we were doing very well both financially and relationship wise. Her father then passed away suddenly and that left her sister without a home. Her mother had passed away years before and being her only close relatives we took her in. The sister is 3 years younger than my wife and is slow. Which is how it is called in the family, can never develop fully mentally. But isn't bad enough to be called retarded and not able to do find work. No special work programs would be used by the family and regular jobs, some people would take advantage of her. No problems for us as we all got on very well and my sister-in-law minded our son looked after the house and my wife worked. My wife got pregnant again and we were very happy, and my sister-in-law got depressed as the pregnancy progressed. So much so even I noticed, I found out the reason from my wife, her sister thought she would never be a mother and that was depressing her. Later on, in the pregnancy my wife stopped sex between us, which had happened during her first pregnancy as well. I had been expecting it to happen, but I wasn't expecting her to bring her sister into our bed with us. Her sister was totally naked and very willing to take over having sex with until my wife was ready to take back over. I was shocked, but I got aroused and so I fucked my wife's sister. Only one rule was told to me no precautions, my wife and her sister had decided for me to father her sister's child. By the time our second son arrived, she was also pregnant and very happy and would have a daughter. Now twenty years later, I've 11 children 5 with my wife and 6 with my sister-in-law. Two sets of twins with her, we still share the same bed and are very happy with our 5 boy and 6 girls. It might not be a normal family these days, but it works for us, and we think it's very special.