Belle has a sweet little girlfriend who has Turrets. Although it is mild, when you pay attention you will notice odd little sounds and squeaks that she makes. One thing in particular that she is doing right now (sounds and quirks change and evolve periodically) is a loud swallowing sound.
Here is an example of peer influence. I have noticed that Belle has started making the same swallowing sounds. Last night at the dinner table she was doing it and her sister Phi pipes up and says "will you knock it off, you do not have Turrets"!
We all roared with laughter. We were not laughing at Turrets, but the peer influence Jo had on Belle and the fact that Phi was the one to point it out.