Desperate younger Sister

My sister always shunned me while going to school I was her nerdy brother, and she was a cheerleader. How things change I left college second in my class and got a great job in my chosen career. My sister scrapped thought and got a crappy job, her looks weren't as wanted as good college scores she found out. That was 2018 and with the pandemic in 2020 her job vanished almost straight away, having loan debt and no income she had two choices go home to our parents or live with her nerdy brother. Of course, she chose our parents, like hell she did, she'd outgrown our hometown and saw it as being a total failure in going back there. Too proud to admit she had failed; she chose to live with me. I'd my own home I was still paying it off, another two years at most it would be mine. I took her in as that what good brothers do, she was unusually quiet for the first month. I paid off her loans she had from buying clothes. Totally relying on me to support her, was a huge shock to her self-esteem. As the lockdown dragged on, she started helping me with my work, as I was working from home. Finally, she decided to reward her nerdy brother for helping her and joined me in my bed. Now sexually active together, I taught her to be a personal assistant. It would give another skill once the pandemic was finished, on the lockdown ending I was promoted, due to vacancies created during the pandemic. Now entitled to my own PA and my sister having been helping me during the lockdown. I decided to give her the job, not just because she was sleeping with me. But it was part of my decision, we worked well together, our problems growing up together gone. I soon got another promotion also due to the pandemic. A senior colleague had caught Covid and had a limited recovery but was hindered somewhat by what they called long Covid. Now I was also entitled to a secretary, who my sister picked for me. She chose the woman she thought was a good match for me. But I didn't show the amount of interest she wanted me to show to the secretary. So, she seduced the secretary and then had her join us in my bed. Now in a sexual relationship with secretary and PA/sister, I was quite happy with my life. My sister arranged for my secretary to get pregnant by giving her fake pills to stop getting pregnant. While my sister took the true pills, watching the secretary who was now also living with us. She told the secretary, the batch of pill they had been using, had been recalled due to problems. Saying some women got pregnant on them others didn't, the secretary never bothered to check and took a home test and got a positive result, my sister also took a test and wasn't pregnant. Encouraged by my sister, I proposed to my secretary, and she accepted. Marrying a month later, Karma had decided my sister needed a lesson. After our son was born, my sister my only lover at the time while my wife recovered for the birth. My sister was using the pill as was usual for her and she got pregnant. Either she missed one or two or one or two weren't up to the standard needed. Either way she got pregnant and would've our daughter. Now linked by a child and blood she has stayed with me and my wife sharing our bed. Two years since the birth of our daughter March tenth, I've two wives you could say and 3 children a boy and two girls, my wife had a girl second time round in 2024. My sister is content to stay in the relationship she has with me and my wife. Only our parents are fully aware of our living arrangements, and they have come to accept it.