Doug Ford's remarks on a Toronto radio station Friday come during a tough week for the mayor in which he admitted having used crack cocaine, and a video was released showing him ranting while drunk.
"I've done my best to advise Rob and it doesn't differ from other people's advice. Sometimes brothers keep things from each other," said Ford on Radio Station AM 640.
The councillor said the mayor's political opponents want him out of the way before the municipal election, next fall.
"What they want to do once he's down there, they want to kill him, because they know if he gets back on his feet, and starts moving forward and gets his life together, they know they'll have one heck of a battle," he said.
"If Rob goes away on a little vacation, a week, two weeks, comes back, loses 50 or 60 pounds, and stays on the straight and narrow … it will be very tough to beat Rob Ford," he said.