One thing that I did in a difficult situation like this is to write the person a letter - that way things are said fairly and no arguement is started. Or print out this page and give that to them.

It's a horrible situation and I'm sorry that you have been put in it, I'm also horrified at the treatment you are receiving from your collegues.

A life is a life be it a chick or a horse. A 4 year old is not old enough to handle the responsibility of a pet, especially not one which is a baby itself.

Perhaps you could suggest she goes to the shelter and gets an calm older cat (which the child should not be able to hurt) explain how the kitten will probably bite and scratch him and ruin their furniture etc etc etc etc

Good luck