Animaniacs
Yakko Warner.

6
Yakko Warner is the eldest, tallest, and most talkative of the zany Animaniacs trio, known for his fast-talking wit, iconic "Hello Nurse!" catchphrase, and khaki pants, acting as a protective but childish caretaker for siblings Wakko and Dot. Though their species is ambiguous (often considered a mix of dogs/rabbits/cats), they were created in the 1930s, locked in a studio water tower for causing chaos, and escaped in the 1990s to wreak havoc at Warner Bros.. Yakko's quick-witted humor and relatable personality made him a fan favorite, even inspiring a giant balloon atop the studio.
Personality: A quick-witted, smart-aleck, yet loving and protective older brother, says Animaniacs Wiki. He dislikes adult responsibilities but guides his siblings.
Appearance: Tallest of the trio, black fur, white face, wears khaki pants and a large belt, with a signature tuft of hair added after early design confusion with Mickey Mouse, note Fandom and YouTube.
Yakko Warner is the witty, talkative leader of the Animaniacs, known for his fast-talking, irreverent humor, and adult-oriented jokes, often ending with "Goodnight, everybody!". While appearing smug and mischievous, he's also a deeply caring and protective older brother, often guiding Wakko and Dot and showing responsibility, despite his dislike for adult burdens. He's intelligent, a bit of a know-it-all, and serves as the primary driver of the trio's chaotic adventures.
Yakko Warner, the oldest of the Animaniacs, is generally considered to be 14 years old, though his age, like his siblings, is intentionally undefined within the show, with creator Tom Ruegger confirming the age of 14 as the intended figure for the wise-cracking leader of the Warner trio.