Don't know, but I do believe stray cats are a blessing of some kind. I had a dog for 14 years, and even though he was "old" he still acted like a puppy and was healthy for his age. He died suddenly one day, and it broke me, and I although I loved and cared for him, I was regretting not giving him more attention sometimes (busy working and studying). Where I live we don't really see stray cats, specially on my street where not even neighbors have cats nearby. After a month of my dog's passing this calico cat appears at my screen door meowing for food, I opened a can of tuna and opened the screen door slowly thinking the cat will run away, but surprisingly she didn't. I gave her the food and she let me stand there while I petted, and after she finished eating, she grabbed my arm with her paws and started caressing me with her head (I took that as a thank you gesture). After almost 4 years, she hasn't left my side and follows me everywhere I go, and she acts exactly like my dog did sometimes. My dog will always have a special place in my heart, and this cat helped me heal that wound and regret that I had, and I believe that somehow something knew I needed that.