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Danica's sister Crystal was in the running for Winnie. So when we can focus on that fact and then say that she ultimately appeared on the show as Becky and mention Ben Savage there as well. Danica McKellar's sited Crystal played Becky and Ben Savage made

1. Danica McKellar almost wasn't Winnie Cooper

It's hard to imagine anybody but Danica McKellar being the object of Fred Savage's affection on "The Wonder Years." But the young actress had some stiff competition for the role of Winnie Cooper -- from her own sister. According to an interview with the L.A. Times in 1990, a then-15-year-old Danica explained that the final two candidates for the part were her and her young sibling Crystal.

Even casting director Mary Buck admitted that "it was practically a tossup." In the end, Danica prevailed. Crystal did get her time to shine on "The Wonder Years," though, playing Kevin's other love interest, Becky Slater, in 10 episodes.

That wasn't the show's only bit of nepotism. In the Season 3 installment "The St. Valentine's Day Massacre," Fred's little brother, Ben, played Cupid. Of course, Ben would go on to score his own sitcom, "Boy Meets World." Now he is set to reprise the role of Cory Matthews in the upcoming sequel, "Girl Meets World."

The 25th anniversary of 'The Wonder Years': What you never knew about the nostalgic series

Can you believe it's been 25 years since Kevin Arnold first set eyes upon Winnie Cooper on "The Wonder Years"? It's true. Although fans grew up with stars Fred Savage and Danica McKellar throughout the show's six-year run, there's a lot you might not know about them and the hit series behind the scenes. Here are 10 fun facts about "The Wonder Years." — Amy and Nancy Harrington, Yahoo! Contributor Network