Alyssa Milano was the kid on the TV show "Who's the Boss" back in the early 1980s with Tony Danza. Pre-cable, it was a middling hit, but its audience was significantly bigger in absolute terms than, say, "Seinfeld" a few years later. Milano's continuing presence in pop culture is probably attributable to the fact that her show was pre-cable. Back then, there was a more homogeneous set of pop culture references, because we all watched the same shows, even if they weren't that good. Hard to believe she's having her 38th birthday today. Of course, "Little Ricky" from "I Love Lucy" is probably going on 60 or so.
Milano went on to star in the cable show "Charmed," of which I have never watched one minute. But she also markets baseball-related clothing for women, which is pretty cool -- apparently she's a big fan.