Both Adam Sandler and Rob Schneider are among the list of comedic greats. They've each had successful films on their own, but they also tend to co-star together.

True, Adam tends to bring an all-star cast whatever creative direction he goes. But fans have noticed that he and Rob Schneider share the screen together more than most.

As CheatSheet notes, the two comedians originally met at Adam's first comedy show in the '80s. Rob found Adam hilarious, and they shared beers after the show and Rob told the newbie that he would do great.

Later, the two would appear on 'Saturday Night Live' and start flexing their comedic chops. Their first film collab was in 'Water Boy,' which came out in 1998, though Rob's role was more of a cameo than an actual part.

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Fast forward a few years, and Rob and Adam would share the screen together 17 more times. In that time, though, Sandler would overshadow his friend and mentor in more ways than one.

Adam's net worth is a jaw-dropping $420 million while Rob's hovers around $12 million. Both figures are significant to the average fan, but Adam Sandler clearly wins when it comes to both notoriety and paycheck size.

But why do the two guys appear in so many movies together? It can't be that Adam feels guilty about surpassing his friend's success, so he's keeping him in the loop. Or can it? Rob told Howard Stern in an interview, "He’s been nice enough to include me in his gigantic success story."

Fans on Quora have a more interesting theory about why the guys are so dedicated to one another, though. While they agree that sure, the comedians and actors are good friends, they're also sticking with each other because of a pact they made early on in their careers.

Quora fan Bob Smith says he heard that a handful of early 'SNL' comedians (including Adam, Rob, David Spade, and Chris Rock, among others) had an agreement. The rumor goes that whichever (if any) of the cast "made it big" after 'SNL,' they'd do right by the rest of the crew.

It does make sense, fans agree, because comedy is a bit unpredictable in a lot of ways. Who would have guessed that Chris Rock would lean heavily toward stand-up while Adam's talents would translate better into running gags and romantic comedy roles?

The theory also explains why Chris Rock is absent from many Sandler flicks; he's so famous in his own right, that he doesn't need a leg up from his buddy's fame.

Of course, Rob might not necessarily need handouts, either. Though it can't hurt to have had a handful of his films ('The Hot Chick,' 'The Animal,' 'Deuce Bigalow') produced by Sandler's production company, Happy Madison Productions.

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