fill somebody's boots/shoes

fill (one's) boots

1. To take or obtain as much of something as one can. Primarily heard in UK. Since the shop announced its going-out-of-business sale, customers have been filling their boots with formerly overpriced homeware.
2. To replace one in some role; to take over for one in some position. You do so much for the company that I don't see how anyone could fill your boots.
See also: boot, fill

fill (one's) shoes

To replace one in some role; to take over for one in some position. You do so much for the company that I don't see how anyone could fill your shoes.
See also: fill, shoe
Farlex Dictionary of Idioms.

fill someone's shoes

Fig. to take the place of some other person and do that person's work satisfactorily. (As if you were wearing the other person's shoes.) I don't know how we'll be able to do without you. No one can fill your shoes. It'll be difficult to fill Jane's shoes. She did her job very well.
See also: fill, shoe
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

fill somebody’s ˈboots/ˈshoes

do somebody’s job in a satisfactory way when they are not there: Mr Carter is retiring and we need a new director to fill his shoes.
See also: boot, fill, shoe
Farlex Partner Idioms Dictionary

fill (someone's) shoes

To assume someone's position or duties.
See also: fill, shoe
American Heritage® Dictionary of the English Language, Fifth Edition.
See also:
  • fill (one's) boots
  • fill your boots
  • beat someone to the punch
  • beat (one) to the punch
  • beat to the punch
  • get (something) for (someone or something)
  • beat to
  • beat someone to it
  • beat (one) to (something)
  • beat (one) to it