Moving on with my sister

I'm Gilbert 37 divorced 2 children, my ex wife didn't want the children only money and so everything was split 30/70. House sold and car sold so she could be free as she calls it, I was left with 2 children 4 and 2 no place to live and only my pay check to keep us. Lucky I had a sister Ashley 34 single who took us in, Ashley works from home and does a lot of different things, artist, writer and internet seller. Our parents are retired and in a retirement village, they were in their thirties when they had us. Ashley's home is 4 bedroom and just outside the town limits and on a big block 12 acres, she likes horse riding and has 5 horses. She bought 2 horses and then got some rescue horses as well with poultry and a dog made her lifestyle till I moved in with her last March. I'm a mechanic and with the help of Ashley am able to work fulltime. Anyway back in April I walked into her stables and caught her masturbating herself and joined in with her. From then on we sleep together all the time and Ashley got pregnant because she wasn't on any protection and didn't bother after we started fucking. Nobody outside our family knows we're brother and sister. With the same surname everyone assumes we're married. The children love Ashly and haven't said anything about their mother since we moved in with Ashley and the youngest has started calling Ashley mommy.