When it comes to making new friends, sometimes mother really does know best. Such was the case with Bill Gates and Warren Buffett.

Gates didn’t want to meet Buffett at first, but his persistent mom, Mary, eventually wore him down and convinced him to. “I’m a technology nerd,” the Microsoft co-founder reflects on his blog. “[Buffett’s] an investor who doesn’t use email. In fact, I never expected to be friends with him.”

The power duo’s billionaire bromance kicked off 25 years ago today. On that fateful day, July 5, 1991, Gates was determined to spend “no more than two hours” with Buffett. But then the “Oracle of Omaha” fired off a flurry of clever questions, one after the other, that no one had ever asked Gates before. “We were suddenly lost in conversation and hours and hours slipped by,” Gates recalls in a touching blog post commemorating the anniversary today.

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They laughed, they related, they bonded, and an “unexpected friendship” was born. “It was a deep friendship from our very first conversation,” Gates writes.

Despite their differing styles (Buffett likes Oreos for breakfast and Gates prefers Cocoa Puffs), the mega moguls were soon thick as thieves. They eagerly swapped book recommendations, battled it out at bridge and stitched up starring roles in each other's sweeping spheres of influence. Sure enough, Buffett is a Gates Foundation trustee and Gates sits on the board of Berkshire Hathaway, because of course they do. That’s what friends are for.

Certain connections have their benefits, especially ones of this caliber. After all, billionaire BFFs stick together like birds of a feather.

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