的毛病

…'s fault

→ 的
phrase Rare #26,295
…'s fault 毛病 can refer to a flaw, problem, or bad habit; 的 links it to the person or thing that has it.
CH: 熬夜是他的毛病。
EN: Staying up late is his bad habit.

我挑不出他的毛病。

I can’t find fault with him.

他总是挑别人的毛病。

He’s always finding fault with others.

至少你们“改”了他说脏话的毛病

At least you’ve “fixed” his habit of swearing.

— 妈咪 (2014)

老爷惯出来的毛病

A bad habit indulged by the master.

— 大红灯笼高高挂 (1991)

这就是她的毛病

That's her problem.

— 蝴蝶梦 (1940)