My wife's sister

My wife Janet 53 had a minor stroke and needed fulltime care and her sister Rachel 56 divorced came to look after her. Janet has always smoked and that's why she had the stroke I believe, Janet wasn't able to do much for herself for a long time, but has improved a lot since. I'm Robert 56 and with Janet have 3 grown children, Rachel was looking after Janet and the house and I went to my job as usual. Rachel would go shopping on the Saturday, when I was home and one Saturday I was horny and fucked Janet while Rachel was out. Janet was really aware of much at the time, on Rachel return she asked me to help bath Janet. It was the first time I saw Rachel naked, Janet was washed and redressed and put back into her bed. I was again horny and straight asked Rachel for a fuck, I didn't expect her to agree, but she did and we been fucking ever since. Janet has recovered enough, so we can have sex with her knowing what is happening. But she isn't as interested in sex as before her stroke. So I fuck Rachel mostly.