[LDandPasquale]

First off, i think the OP'er isnt asking to come over ....the bf's parents are inviting them. I think the OP'er would be just as happy staying at home with her little furbaby. The Bf's parents are WANTING them to come over to visit. Also, THEIR OWN CHILD is allergic to the cat. That being said......seems a bit selfish to me.
I'm a person that believes that what a person does now can effect the outcome of a later event. For instance, what happens if the OP'er and her bf get married and have a little baby? As we all know, some animals do not like babies....and as we can see this cat is a hunter. I would be fearful to bring a baby over there...so what will the inlaw do then? I mean she wont even put the cat in another room for THEIR OWN CHILD who is allergic.

Now as far as my dog being just a "PET". My Pasquale is NOT just a pet. To me he is my child. I do not have children due to reasons i wish not to discuss. However, my entire family and extended family (including my work) knows how much my dog means to me. So if anyone says something bad about him...they are going to get a mouthful back from me...including "little old ladies". Being older does not give anyone the excuse to being rude. Respect is respect and you do not lose that cause of age. Yes you forget things as you get older(usually events and names)...but you do not forget how to be respectful...UNLESS you were never respectful to begin with.

I would say calmly explain to your bf's parents that Leo is part of your life now and its a package deal now. Perhaps you can drop Leo off at your parents for the day and then sleep at your parents house at night. That way you are WITH Leo and your bf doesnt suffer with his allergies. And if you and your bf are serious and plan on getting married in the long run and having kids..i would ask them what their plans are for the cat when you bring your child over.

Hope it works out for you!!