That phrase sounds like a compliment until you realize it is usually just another way of saying the one we expect to absorb the damage.
My younger sister Lily was the opposite of me in ways people found charming because she was beautiful enough to get away with it. She was funny, impulsive, dramatic, warm when she wanted something, cold when she didn’t, and somehow always forgiven before she had even finished making the mess. Growing up, Lily crashed cars, dropped classes, lost jobs, borrowed money, dated men who looked like bad decisions in human form, and then cried hard enough that our parents somehow turned every disaster into a weather pattern everyone else was supposed to endure on her behalf.
I was the responsible one.
Lily was the fragile one.
That division explained more of my family than any therapist ever had to.