Luigi

Luigi is the younger twin brother of Mario.

Super Mario World 2: Yoshi’s Island
The Stork carrying Mario and Luigi was attacked by Kamek, and both Luigi and the Stork were kidnapped while Mario fell down onto Yoshi's Island. Once the Yoshis saved them from Bowser, the Stork once again set off to bring the brothers to their parents.

Yoshi’s New Island
The stork accidentally delivered Mario and Luigi to the wrong house, and while he was taking them to the right house, he was once again attacked by Kamek. Luigi was captured and taken to Bowser's hideaway on Egg Island. After the Yoshis defeated a time-travelling adult version of Bowser, Mario and Luigi were reunited once again and taken to the correct parents.

Yoshi’s Island DS
Kamek and a number of Toadies kidnapped several babies, including Luigi. The Stork managed to save Mario and Peach, but Luigi was still captured. After defeating both the older and younger versions of Bowser, the Yoshis saved all of the kidnapped babies, including Luigi. Both he and Mario were delivered back to their home.

Personality
Luigi gets scared very easily.

Physical Appearance
Luigi's exact height is not currently known, but it's currently estimated at 1.71 m (~5'7").

Abilities
Despite Mario being known as Jumpman, Luigi is actually better at jumping than him.

Luigi can also run on water for a brief amount of time.