Returned to run Family Business

I'd been working overseas and doing quite well, my father passed away suddenly (stroke). So, I returned to take over running the family business as the oldest of two. While overseas I'd been very sexually active, fucking the hired home help, who were very willing to please. All mature and passed getting pregnant, I 31 found it simpler just to fuck the hired home help then go out chasing women. On my return there wasn't any hired home help just my mother 55 and sister 27, I take after my father who was very assertive. My mother was compliant as was my sister and I assumed my father's roll as head of the family. But lack of regular sex soon got me a bit frustrated, use to getting home from work and fucking the home help. My sister usually was in her room doing a painting, my mother made the dinner usually. That evening dinner was still cooking another hour I was told, no problem. Then on the spur of the moment I asked my mother if she had anything she had do before dinner. No was her response, so I told her to join me in shower to wash my back. Expecting a refusal and mainly seeing how she would respond. OKAY was her response and so I went with her to the bathroom, showering together she washed my back and I hers. I got aroused and fucked her in the shower, she just let me after dinner and everything put away, my sister back to painting. I took my mother to her bed and fucked her again; this became my regular sexual relaxation. My mother just allows me to fuck no fuss or refusal anytime I wish. So, much so I started sleeping in her bed every night sex or no sex. After several months, my mother took ill gall stones and had to go into hospital. With my sister doing the cooking and I again decided to see what response I would get from her. I asked her to join me in the shower and wash my back, she did and like with my mother I fucked there and later in our mother's bed. Only made one mistake, not used to taking precautions myself I failed to so, my sister was a virgin till I fucked her and with no precautions she got pregnant. Whether the first second or third fuck I don't know or care. she gave me a son. Sold up the family business moved interstate bought another business and live with my mother and sister and son. Still fucking both my mother and sister, no precautions taken either. As far as anyone outside our family group knows my sister is my wife. I've always been taught that I'm entitled to whatever I wanted by my late father.