There have been literally millions of chips implanted with no ill effects, so I hope that can be comforting. It is also teh only way MANY cats have found their way home when they got into trucks and were carted many miles from home.
Having them neutered is the best thing you could have done, cats in heat are very annoying (and almost constantly are until they get mated) Vaccines I recommend after having a whole litter of beautiful kittens die in my arms, and their mother, after she was dumped pregnant on my doorstep with distemper. Thank God my house cats were vaccinated or they could have died too. It ripped through the neighborhood like a plague. The side effects of these vaccines are a LOT less dangerous then your cat getting the disease.
You will be blessed for taking in these cats, you are an angel here on earth and I wish you the very best of luck!
Having them neutered is the best thing you could have done, cats in heat are very annoying (and almost constantly are until they get mated) Vaccines I recommend after having a whole litter of beautiful kittens die in my arms, and their mother, after she was dumped pregnant on my doorstep with distemper. Thank God my house cats were vaccinated or they could have died too. It ripped through the neighborhood like a plague. The side effects of these vaccines are a LOT less dangerous then your cat getting the disease.
You will be blessed for taking in these cats, you are an angel here on earth and I wish you the very best of luck!