The Health Diagnosis Millie Bobby Brown Has Dealt With Since Birth

Many celebrities live with difficult yet invisible conditions, including "Stranger Things" superstar Millie Bobby Brown. In fact, her health diagnosis may be particularly surprising to fans given her awards and accolades as a performer.

According to a 2017 Variety interview, Brown was born with gradually worsening hearing loss that affected one of her ears. This condition is known as unilateral hearing loss, and it affects around 5% of people in the United States (via Cleveland Clinic). Brown isn't the only Hollywood actor with unilateral hearing loss; actor Rob Lowe and late-night host Stephen Colbert have the condition as well.

The Variety article mentioned that Brown tried ear tubes to restore her hearing when she was much younger. Ear tube surgery, called tympanostomy, can work for some people — especially children — if their deafness or partial deafness is related to fluid buildup that needs to be drained from the middle ear canal. But for Brown, ear tubes didn't work, and she gradually lost her ability to hear any noises  in one ear.

While partial deafness hasn't slowed down Brown's ability to act effectively, it's hindered her ability to catch details on set, such as director and crew announcements. As Brown noted during a 2025 "Call Her Daddy" podcast appearance, "I do miss very important things in my life, like, 'cause I can't hear." She also explained that she can't hear noises around her when she chews food; instead, she just hears the chewing.

Indeed, Brown's explanation of her daily hearing experiences makes sense. She hasn't completely lost her hearing, of course, but science shows that the brain performs best when it's able to process sounds from both ears. Therefore, when it only receives input from one ear, it may not interpret noises (or their sources) accurately.

In certain cases, losing your hearing can have side effects related to speech, too. This phenomenon was discussed in a 2024 article in the Journal of Voice. The article named several notable verbal side effects in children with partial hearing loss, including a tense-sounding voice, breathiness, and harshness.

Brown hasn't opened up about exhibiting any unusual vocal traits in her past. On the contrary, she has sung with Nicki Minaj, telling Variety, "I just started to sing, and if I sound bad I don't care, because I'm just doing what I love."

Partial deafness can affect more than just a person's hearing or speaking ability. It can also cause psychological and social difficulties, including episodes of anxiousness or social withdrawal. In the past, Brown has admitted to having anxiety. PopCrush reported in 2020 that Brown tackled anxiety that was related to being constantly in the media. To help quell her stressors, Brown said she liked to drive and fuel her creative desires. The article didn't mention whether or not her impaired hearing amplified her anxiety.

(On a somewhat related note, one of Brown's "Stranger Things" costars, Gaten Matarazzo, has a rare disease.)