Pamela Hayden who voiced the character has officially announced her retirement from the show.

Pamela Hayden, who has worked on the show since 1989 and has voiced over 700 episodes, officially announced her retirement from the hit animation, saying the time had come to 'hang up [her] microphone.'

In a statement, she continued: “It’s been an honour and a joy to have worked on such a funny, witty, and groundbreaking show... I’ll always have a special place in my heart for that blue-haired 10-year-old boy with glasses.”

Milhouse van Houten, the best friend of Bart Simpson, is a well-known recurring character in the show for the past 35 years.

Producers plan on re-casting the role of the shy, easily led schoolboy in the coming months.

But the blue-haired character, who is said to be named after former US president Richard Milhous Nixon, isn't the only one voiced by Hayden. She also portrayed Ned Flanders' sons Rod and Todd, school bully Jimbo Jones, Lisa Simpson's friend Janey, and Chief Wiggum's wife Sarah.

Milhouse is definitely her most popular character, with Hayden even sharing that people would come up to her quoting Milhouse lines.

She explained: “People are always saying what a nerd he is, but one thing that I love about Milhouse is he’s always getting knocked down, but he keeps getting up.

“I love the little guy. It’s this wonderful analogy for life.”

Creator of The Simpsons, Matt Groening, commented on the departure: “Pamela gave us tons of laughs with Milhouse, the hapless kid with the biggest nose in Springfield. She made Milhouse hilarious and real, and we will miss her."