Cancer Fresca

I'm going to start this by saying, if you have cancer or AIDS, don't be offended... My family is just weird.

I take a Fresca from the cooler on the deck.

Brother 1: NO!!!! Don't drink that one! It has cancer!

Me: What? (thoroughly confused and a little nervous)

Brother 1: There are some Fresca's that have cancer, and other ones that have AIDS, you have to be careful which ones you drink.

Me: You're not serious.

Brother 1: No, really, that one has cancer.

Me: How can I tell which ones are ok?

Brother 1: You can't, only Cousin J and I are able to tell which ones have cancer and which ones have AIDS. We can also tell which ones are the cancer dissolving Frescas. We haven't found an AIDS dissolving Fresca yet, so don't drink the Fresca in the basement, you'll get AIDS and we won't be able to cure you.

I choose another Fresca from the cooler.

Me: So, what about this one? Is this one ok to drink?

Brother 1: Yeah, that one's fine, don't worry.