Will’s older brother in “Stranger Things” is Jonathan Byers. Jonathan is the firstborn son of Joyce and Lonnie Byers, while Will is the younger brother whose disappearance launches the show’s central mystery.
Portrayed by Charlie Heaton, Jonathan is introduced as a quiet, withdrawn teenager and an aspiring photographer. His reserve is partly shaped by family circumstances: he is protective of Will and often acts as a second caregiver because their father is largely absent. When Will vanishes in the first season, Jonathan blames himself for not doing more to protect him.
Jonathan’s photography also helps him investigate the supernatural threat. A photograph he took at Steve Harrington’s house contains an image of the creature later recognized as the Demogorgon. He teams up with Nancy Wheeler, and the two help uncover the truth about Will, Hawkins Laboratory, and the Upside Down. A common mix-up is reversing the brothers’ ages: Will is the younger Byers sibling, while Jonathan is the older one.