She was always PRONE to melancholy.
Game of Thrones Season 4, Episode 8
Perhaps even taller, smarter
and less PRONE to freckling.
The Big Bang Theory Season 1, Episode 15
If I was PRONE to sarcasm...
The Big Bang Theory Season 6, Episode 19
Humanity is disorganized,
PRONE to destruction.
Westworld Season 3, Episode 8
...who's PRONE to canker sores
and pinkeye?
The Big Bang Theory Season 4, Episode 23