Stork

The stork is a supporting character in the Yoshi's Island series. It is responsible for delivering Baby Mario and Baby Luigi to the home of their mother and father. This is a reference to the myth of real life storks delivering babies to young couples. Its design is also based on the, the same stork told in folklore.

Super Mario World 2: Yoshi's Island / Yoshi's Island: Super Mario Advance 3
In the prologue Super Mario World 2: Yoshi's Island and Yoshi's Island: Super Mario Advance 3, on its way to deliver the babies, the stork is attacked by Kamek, who wants to kidnap the young brothers before they mature and cause trouble to the Koopas. Kamek succeeds in kidnapping only Baby Luigi and the stork.

After Yoshi defeats Baby Bowser, Baby Luigi and the stork are rescued. The stork then carries the babies to their parents.

Yoshi's Island DS
In Yoshi's Island DS, the stork is not only helping the Baby Mario Brothers, but also Baby Donkey Kong, Baby Peach, Baby Wario, and Baby Bowser. The stork is more of a major character in this game as it is shown traveling with the babies in cut-scenes, and it helps even more by bringing babies to Stork Stops. In the end, more than one stork are seen; several storks carry the babies back to their homes.

Yoshi's New Island
In Yoshi's New Island, the stork discovers that the parents it delivered the babies to in the original game are not Mario's and Luigi's. While it tries to find their real parents, it is attacked by Kamek and drops them again. Baby Mario is saved by Yoshi while Baby Luigi is captured by Kamek again. It is also revealed that the stork and other storks deliver infants from a magic land in the sky.

Super Smash Bros. Brawl
In Super Smash Bros. Brawl, the stork appears as a sticker. The sticker shows the stork carrying Baby Peach. In The Subspace Emissary, the sticker can be used by any character to raise their body- and spin-based attack power by twenty one points.

Super Smash Bros. Ultimate
The stork appears in Super Smash Bros. Ultimate as an Advanced-class support spirit. When used, it gives air resistance to characters, making it harder for strong winds to blow them around.

Mario Kart Tour
In Mario Kart Tour, the stork makes a cameo appearance on the Baby Mario Hanafuda glider.

Other appearances
The first actual mention of a baby-carrying stork in the Mario franchise is in The Super Mario Bros. Super Show! episode "Mario of the Apes". When the gorilla couple June and Ward are waiting for a child of their own, they mistake an Albatoss that drops Mario on their porch for the actual stork.

The stork is mentioned again in Super Paper Mario about bringing Captain Gills his own children.