Luigi’s turning 30 this year, which is well past the “oh, look at the cute baby plumber” stage. But Princess Peach forgot to bake him a cake, and you neglected to get him a gift … again.

Shame on you! We remembered his birthday. Well, actually, DePaul University in Chicago told us (but don’t tell Luigi that).

Even after 30 years, says assistant professor of game development and interactive media Jose Zagal, he’s still “player two” — the Robin to Mario’s Batman.

DePaul University/Jeff Carrion“Though Robin was young and inexperienced, he was portrayed as competent and even somewhat cool,” said Zagal, who works at the university’s College of Computing and Digital Media and authored The Videogame Ethics Reader. “Luigi, however, is often portrayed at best as a clone of Mario and, at worst, the more cowardly brother who still pulls through in the end.”

Luigi made his debut in 1983, two years after Mario appeared as a carpenter in the original Donkey Kong. While Mario has taken on many roles — doctor, teacher, and all-around unlicensed professional (he can’t be that talented) — Luigi’s just … Luigi.

“Due to technical constraints of the era, the color of overalls was the best means to tell the characters apart,” said Zagal. “Luigi started as a simple palette swap of the Mario character and has continued to live in Mario’s shadow.”

Life’s not all bad for the green-clothed Italian. He has starred in two of his own titles: the unpopular educational game Mario Is Missing! (although that’s still kind of about Mario) and Luigi’s Mansion for the Nintendo GameCube, which is getting a sequel this year for the 3DS called Luigi’s Mansion: Dark Moon.

That’s still crumbs compared to the fame Mario has achieved, which makes Luigi ever the underdog. Perhaps that’s why Zagal thinks we should appreciate him a bit more.

“Luigi’s cowardice makes him more relatable and interesting as a character,” said Zagal. “As a player that makes him a better partner; he’s a reluctant hero, and it’s thanks to the player that he can — temporarily — overcome that. Heroes need to be human, and Luigi has more of that than Mario.”

DePaul University might have marked their calendars early, but we at least tried to show our appreciation for Luigi in some small way. Below is a (non-comprehensive) gallery of his design changes through the years — kind of like a photo book. That’s our present to the poor, unloved brother. Maybe you could at least send him a card?