keep watch over

keep (close) watch over (someone or something)

To guard, protect, or ensure the welfare of someone or something, often through close observation. I felt better sending the kids to camp when I knew Mrs. James would be there to keep close watch over them. I can't help but feeling that I had an angel keeping watch over me that day.
See also: keep, over, watch
Farlex Dictionary of Idioms.

keep watch over someone or something

to supervise someone or something; to take care of someone or something. Please keep watch over the project. Will you keep watch over Timmy for a minute?
See also: keep, over, watch
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • keep (close) watch
  • keep (close) watch over (someone or something)
  • keep a (close) watch
  • keep watch
  • watch over
  • keep a close watch over (someone or something)
  • stakeout
  • send (one) round the twist
  • nature abhors a vacuum
  • send (someone or something) by (some means)