Once upon a time, a little boy lived in Philadelphia under the name of Saladin Paracelsus de Lambertine Evagne von Smith. His father claimed that his son was bright as a button, and so the name "Button-Bright" was soon applied to the boy, a nickname that stuck.
One day, the little lad vanished from his home and found himself by a road that turned out to be in a land across the desert from the Land of Oz. Baum never specified particularly how Button-Bright was so far away from his home. In my book, Outsiders from Oz, the first chapter reveals that he was playing with an old watch in the backyard when he disappeared. All else we know is that he was wearing sailor clothes, a fashion for young children back in those days.
Fortunately, Dorothy, Toto and the Shaggy Man found him and took him with them to Foxville, where King Dox of Foxville took a liking to Button-Bright's inquisitive and simple nature (his answer to most questions would be a simple "Don't know") and gave Button-Bright a fox's head, which the young boy had to wear until they found the Truth Pond in the Land of Oz.
Button-Bright allowed Baum to have a child character younger than Dorothy simply marveling at the wonders of fairyland, which was basically the entire theme of The Road to Oz. Except for the Scoodlers, Button-Bright is amazed and enthralled by what he sees, even being the lone fan of the Musicker's naturally-produced music.
At the end of The Road to Oz, Santa Claus recognizes Button-Bright and when the boy is sent home in one of the Wizard's bubbles, Claus promises to make sure the bubble sends him home.
Button-Bright, unlike Dorothy, didn't return to Oz very quickly, and in a rare case, when he next appeared in the book Sky Island, he's grown older and more mature. We have no idea how many years passed between Road and Sky Island, though it seems there was a shorter gap between Sky Island and The Scarecrow of Oz. (Joe Bongiorno's Oz timeline puts Road at 1905, Sky Island in 1908, and Scarecrow in 1909.) Road tells us that he was two or three years younger than Dorothy. Seeing as she was probably about eleven by then, I'm going to guess he had probably just turned eight in Road, but has grown to ten by Sky Island.
Button-Bright's role in Sky Island is quite different. Baum had established the Trot/Cap'n Bill duo in The Sea Fairies, and by all appearances he decided to add a character from the Oz books to not only attract more readers, but also try his hand at a young male protagonist. If Scarecrow was indeed the third "Trot" book initially, it seems he had determined to make Button-Bright a recurring character.
Button-Bright takes his family's ancient umbrella and discovers that it will fly its bearer anywhere they want to go, so long as they hold on to the handle. After doing a little visiting around the US, he visits the Pacific Ocean, happening to land outside Trot's home. After telling his story and proving the magic power of the umbrella, the three decide to go to a distant island they call "Sky Island." However, the umbrella carries them to the actual Sky Island: an island floating in the sky!
The three run afoul of the Boolooroo of the Blues of Sky Island, who confiscates the umbrella and makes the three work for him. However, Button-Bright manages to steal the Royal Record book as he tries to recover the umbrella just before they escape to the Pink Country. However, soon Baum's preference for heroines takes over and Button-Bright simply just aides Trot and Cap'n Bill as they wind up conquering both the Pinks and Blues and finally returning home.
Button-Bright rejoins Trot and Cap'n Bill in The Scarecrow of Oz, in which he is found in the Valley of Mo, lost in a snowdrift of popcorn, having taken the umbrella and flown away with it.
Button-Bright contributes little to the plot of Scarecrow, getting lost a few times, leading me to suspect that he may have had a bigger part in Baum's original story concept but his action was deleted when the Scarecrow was introduced to the plot. He arrives in Oz with Trot and Cap'n Bill and stays there, never to return to his home again, becoming good friends with Ojo the Munchkin. (A woefully underdeveloped friendship in the Famous Forty, though writers outside of it have worked on it.)
Was Button-Bright a successful character in creating a male child protagonist for Baum's books? I'd have to say no, even though he is one of my favorite Oz characters. Baum's Button-Bright is three different versions: the "Don't know" child of Road, the boy hero of Sky Island, and the boy who is always getting lost in Scarecrow and onward. Although Button-Bright's actions help resolve the plots of Sky Island and Lost Princess, every time he appeared, Dorothy or Trot would overshadow him. Some may find it liberating that female protagonists were preferred in Baum's tales, but characters like Button-Bright lead us to ask if it was because that Baum just didn't know how to have boys lead an adventure. He could have men—such as the Wizard, the Scarecrow, the Tin Woodman, Cap'n Bill and the Shaggy Man—take a lead role successfully, but when he put a boy in the lead, a female character would usually take the spotlight, unless the boy was a teenager or the star of a short story. Tip is a rare exception, but even he is arguably overshadowed by the Scarecrow and Tin Woodman, and we know how his story turned out.
However, that is Button-Bright viewed through literary criticism. If we instead to look at the Oz books (and related work) as a consistent history with a few historian gaffes here and there, Button-Bright becomes one of the most developed characters of the series. Starting out as a young boy, his experience in fairyland gives him a lust for traveling to strange places. When he grows older and finds the magic umbrella, he is finally able to live out this fantasy. But when he finally is given one of the most wonderful places on earth—the Land of Oz—as a place to roam in, he becomes tired of organization and wanders off on his own, getting lost as Baum describes it. Perhaps he has problems paying attention or, as a friend once suggested, he has Aspergers' syndrome. Whatever the case, it's fortunate that he has friends like Ozma watching out for him.
Perhaps I wound up making Button-Bright a favorite because he made it clear that Oz was a place for boys as well as girls, a point I appreciated at a young age. Today, he's one of many points that make it clear that Oz is simply a place for anyone.