keep someone up at night

keep someone up at night (third-person singular simple present keeps someone up at night, present participle keeping someone up at night, simple past and past participle kept someone up at night)

1. (informal, figuratively) To worry, to disturb, to give someone sleepless nights.
   • 2023 March 9, Sauli Niinisto, 9:23 from the start, in Finland's President Sees No Reason to Talk to Putin‎^[1], Bloomberg, archived from the original on 09 March 2023:

     Reporter: You share this border, more than eight hundred miles, with Vladimir Putin. What keeps you up at night?
     Niinisto: Nothing keeps me up at night. But in the daytime we... like I have said, we are not afraid, but we are fully awake.

• keep someone up late