My family and I left to go on a 1 day trip to a lake, but I have been taking care of a stray and her kittens, so I left some food in their bowl for an early dinner. I came back home early afternoon and find that the mama cat is still here, but her entire litter of 4 have disappeared. What could have happened to them? Did they get hungry and run off by themselves? All of the kittens have been eating solid food. They are almost 2 months old and there is no sign of them.