Baby Luigi
Baby Luigi is a character in Nintendo's Mario series, who is very similar to Baby Mario. He is the infant version of Luigi, although he has appeared in Mario Kart: Double Dash!! alongside his older self. It is generally accepted that these games do not have storylines and merely offer extra playable characters for greater variety. Baby Luigi first appeared in Super Mario World 2: Yoshi's Island where he got kidnapped by Kamek Koopa, only to be rescued by his brother Mario and Yoshi later on. Like his older self, Baby Luigi is voiced by Charles Martinet.
Baby Luigi more recently appeared in Yoshi Touch & Go, where Yoshi must rescue Luigi by throwing eggs in order to hit the Toadies carrying him. In the multiplayer mode, the second player's Yoshi will be carrying Baby Luigi instead of Baby Mario.
Baby Luigi rides along with Baby Mario in Mario Kart: Double Dash!! in a converted baby carriage and appears in Mario Superstar Baseball as unlockable character with speed ability.
Baby Luigi also stars in Mario & Luigi: Partners in Time, along with Baby Mario, his older self, and Mario. His abilities in battle appear to be identical to those of Baby Mario. The game explains the co-existence of the two sets of brothers in this game by saying that Mario and Luigi are sent back in time after an experiment with Princess Peach goes terribly wrong. They must battle the evil Princess Shroob to restore order to the shattered past of the Mushroom Kingdom.
Much to fans dismay Baby Luigi will not be playable in the new Yoshi's Island 2, but people think he'll cameo along with the other kidnapped toddlers in the game. Some also think he might be playable at some point maybe through unlocking him whether its at a point in the game or beating the game, however this is unlikley to happen.
Although Baby Luigi is an extreme crybaby, he seems to be less cowardly than Luigi.
Mario Superstar Baseball Bio
The younger of the Baby Mario Brothers. After being abducted by Kamek, he was rescued by Yoshi and Baby Mario. If you see him and Luigi in the same game, try to ignore the temporal paradox. Baby Luigi is quick around the bases but he doesn't hit for power. He is, after all, a baby.