Kelly Macleod
Macleod will make her debut as the character on Sunday's season finale "Estranger Things."
Macleod's debut will see Milhouse in a minimized role, as the character only has one line in the episode — and will appear in a scene where he, Bart, and Lisa are all adults, so all of their voices will probably sound a little different from their usual adolescent selves.
Macleod previously appeared on The Simpsons in 2022 in the season 33 episode "Bart the Cool Kid." She performed the song "Two Badges, One Mind" in the ep, which also starred The Weeknd and Michael Rapaport.
The musician began her career as a member of the rock band Private Life, which released two albums produced by Eddie Van Halen and Ted Templeman. The band's song "Touch Me" was featured on the soundtracks of both Wayne's World and Gremlins 2: The New Batch.
In 2009, Macleod acted in the short film Slice of Pie, and spent a decade with another band, The Sweet Potatoes. She released a solo album, Wide Open, in 2021.