I have family that truly believes that all snakes are venomous and that if Quetzal should ever bite me, my skin will turn black around the area and fall off. They also believe that he's completely capable of constricting me to death at his current size of 2ft and that in a few years he'll grow large enough to eat my cat and their dogs (all breeds that are 50+lbs). They're positive he'll grow to be large enough to swallow me whole and that it's a good thing I have locking clips on my tank as otherwise he'd get out and make babies in the wilderness of Pennsylvania. It's not phobia but misinformation spurring their fear and, quite frankly, rudeness. I have no separate snake room so when they're visiting my apartment they're going to see the tank on the now-defunct dining room table.
On the other hand I have friends that are absolutely terrified of snakes remarking on how calm and laidback Quetzal is when I take him out even though they won't get near him, touch him, or even look at him. They are truly interested in the way he's kept and the way we interact, even though they say they could never do it themselves. When they say something spurred on by misinformation and myth, and I correct them, they're always interested to know how they might be wrong and adjust their knowledge accordingly, even though they don't want to have anything to do with snakes.
There's a difference between the two and I think finding out which one your cousins side with should be first.