She’ a math genius. She helped develop what’s come be known as the "Chayes-Mckellar-Winn-Theorem" while she was a mathematics major at UCLA. And, she has an Erdos—Bacon number of 6. A team of five were sent to investigate what the fuck either of those things are. Results are still pending Who she was:
McKellar is familiar to most as Winnie Cooper, the girl next door and main love interest of Fred Savage’ Kevin Arnold in The Wonder Years. The on-and-off romance lasted the entire series, like a far less annoying "Ross and Rachel" for kids.
She also became a source of many crushes for developing boys across America, and probably some paedophiles’.