Rule The Roost Meaning

(idiomatic) To be the controlling member(s) of a family, organization, or other group.

Example: 1857, Anthony Trollope, Barchester Towers, ch. 3:
  His was biding his time, and patiently looking forward to the days when he himself would sit authoritative at some board, and talk and direct, and rule the roost, while lesser stars sat round and obeyed.
  Note: Some copies have "rule the roast" in this passage.
1915, John Galsworthy, The Freelands, ch. 16:
  Felix (nothing if not modern) had succumbed already to the feeling that youth ruled the roost.
2004, Kate Betts, "9 Rei Kawakubo", Time, Feb 16.:
  At that moment in fashion, French couturiers ruled the roost.