on someone's coat-tails

on (one's) coattails

Benefiting from someone else's success; using someone else's success as a means to achieve one's own. Everyone knows you've been on the governor's coattails these last two years, but once her term ends, you'll be on your own. A: "I can't believe Jonathan got his paper published in that prestigious journal." B: "Oh, it's only because he's on his professor's coattails."
See also: coattail, on
Farlex Dictionary of Idioms.

on someone's coat-tails

undeservedly benefiting from another's success.
1964 Economist Mr Robert Kennedy cannot be sure of riding the coat-tails of Mr Johnson in New York.
See also: on
Farlex Partner Idioms Dictionary
See also:
  • on (one's) coattails
  • on somebody's coat-tails
  • on someone's coattails
  • on the coattails of
  • on the coattails of (someone)
  • on the coat-tails of someone/something
  • ride (on) the coattails of (someone)
  • ride (one's) coattails
  • ride on coattails
  • ride on someone's/something's coat-tails