Jay Harmer was an 18 year old british male who featured in two GTA V videos titled "Literally Cancer" and "Two More" as part of Make A Wish. He later featured in a video with Dan, Matt and musical comedian Jay Foreman called Nerd³ Plays... Tiny Planes - With Two Jays!. Jay also appeared in the Red Nose Day streams as part of the Cards Against Humanity game with Matt and Dan, where he later said that he was disappointed that no "cancer cards" came up, which is apparently the only time that has happened when playing it.

He first came in contact with Nerd3 through Starlight Children's Foundation at the age of 15, during or after having survived cancer. The two were supposed to meet to play video games together. However, the meet sadly had to be postponed, as Jay's cancer resurfaced before it could take place.

Three years later, he had beaten the cancer for a second time. In February of 2017, at the age of 18, his wish finally came true, and he got to meet and play GTA together with Daniel and Matt.

On March 10th 2018, a video entitled "Nerd3 is in Hospital" was uploaded to the Nerd3 channel. In it, Jay reveals that he is back in the hospital, as his cancer has returned for a third time. He also says that no treatments are working, and that he is not expected to live much longer. Despite the circumstances, Jay remains cheerful, and even encourages everyone to send him jokes about his situation.

Jay also appeared in two more videos with Dan, Matt and Jon where they played Star Trek Bridge Crew together. The videos subtitles where both Star Trek puns based on Jay's name, Nerd³ Plays Star Trek VR: The Next Jay-neration (The Next Generation) and Nerd³ Plays Star Trek VR: Deep Space Jay (Deep Space 9). The latter of the videos started of with a very awkward moment, courtesy of Jon.

Unfortunately, on the 28th of June 2018, Jay passed away after a battle with cancer lasting over 5 years. People from around the extended Nerd³ community and many fans payed their respects on Twitter and Reddit.