A very rainy weekend

I'm Allan 55 divorced 3 grown children, all left home. I live alone on my farm and sister Mabel 52 widow of 2 years came for a visit 3 weeks ago, her 2 children have moved on as well. I bought the farm from parents when they retired twenty years ago. No one in the family wants to take it on now. I make a fair living off it and enjoy the peaceful life here, nothing flash. Mabel missed the farm where she grew up and came for a visit for old time sake she said. Anyway she looked over the farm and the memories came flooding back she said. A week after she arrived large rain storms came thru the area, causing flooding and such to the lower areas. But not a worry to us, but on the Saturday morning it was raining hard outside and the TV wasn't working and being bored we play cards. Nothing much else to do, after a time even cards became boring. I asked Mabel What did you do when you were bored when Frances was alive. She said We would stay in bed and have fun, I nodded and then said I'm up for some fun if you are. She looked at me and said I could use a good fuck, do you still have one in you. Well lets find out I answered, I got up and took her hand and we went to my bed. That was the start of our sexual relationship, we had sex almost every day since and she leaving tomorrow to get her things and then returning live here. She has told her children that she is moving back to the family farm and is giving her home to her daughter Lindsay and her husband David as they don't have their own place. Richard her son is happy to see his mother is moving on with her life and they know they can always visit on the farm. None of the children know of our sexual relationship.