Dorayaki
King Bowser
Well this is the awkward feeling when Tennis Fever and the Mysterious Book are announced together. Or should say, Nintendo obviously notice that when they planned the two games in the same work period, yet they don't want to have babies involve in the Mysterious Book.
And I'm definitely not a fan of Baby Waluigi--- in terms of not even giving his baby form a proper origin explanation in a major game first. Actually, baby magic had appeared in several 1990's TV series episodes and I acknowledge that it can be used in some storytelling, especially for Baby Rosalina who isn't exactly canon to Yoshi, but I feel like they shouldn't be used in spinoff rosters since in this case "babies" are entirely alteregos rather than independent characters, and fans have been criticizing the use of alteregos in rosters. But since Yoshi series was the most reasonable place to keep babies active in their main roles, it's arguable to reject their partcipation recently as if their root is removed.
Another thing that made Yoshi "series" different from the rest of Mario universe branch series, including Donkey Kong Country and Warioware, is its lack of exclusive main cast (if we don't count the colorful "Yoshis" as a cast). Yes Yoshi isn't the only regular in this series, we got babies, Bowser and Kamek, but they also consist of the reason why Yoshi is considered as a Super Mario prequel rather than its own series. Still, I think Yoshi series has the potential to pull a story without relying on the premise of Super Mario if they just don't want to go back to make baby stories and prequels.
Birdo sure stands out as main part of the question since she's a modern main cast and portrayed to be Yoshi's counterpart in some spin-off occasions, but never made a real Yoshi game appearance. Additionally, despite the original SMW describes Yoshi Island as a home for various dinos, they're not shown in later Yoshi games.
Do you think Yoshi series needs a distinctive "main cast", or should go back to focus on baby stories? Or you think this series is fine with the focus on Yoshis?