Byron Trott is on a roll.

BDT Capital, the firm set up by the former Goldman Sachs banker, is advising Mars Inc., the maker of candy and pet food, on its $9.1 billion deal to buy the animal hospital company VCA Inc.

BDT is working alongside Morgan Stanley on behalf of Mars and is expected to share in $30 million to $35 million in fees, according to estimates from Freeman & Co.

Barclays is advising VCA and is expected to receive $35 million to $40 million in fees.

The deal follows Mars' acquisition of Wrigley, the chewing gum company. In October, Mars took full control of Wrigley after it bought Warren Buffett's stake in the company.

Buffett originally teamed up with Mars to buy Wrigley for $23 billion in 2008. Trott brought Buffett into the deal, with the billionaire investor putting $6.5 billion of his own money into the transaction.

The Mars-VCA deal is the latest in a long line of transactions for Trott, who is known on Wall Street as Buffett's favorite banker. In 2004, Buffett mentioned him by name in a letter to Berkshire Hathaway investors.

"He understands Berkshire far better than any investment bank with whom we have talked and - it hurts me to say this - earns his fee," Buffett said.

Trott told Fortune magazine in 2014 that his company works only with "billionaires with businesses." For instance, in May 2016, BDT advised JAB Beech, an Austrian company, on its acquisition of Krispy Kreme Doughnuts for $1.3 billion, according to data from Thomas Reuters.

BDT also advised Carlson Hotels on its sale to China's HNA Tourism Group and is advising Guardian Industries on its deal with Koch Industries. The firm also advised Cox Automotive on its $4 billion deal for DealerTrack Technologies, and Exor on its $6.9 billion deal for PartnerRe.