The gamer, whose real name is Mark Fischbach, appeared alongside his 19-year-old niece Miranda's father to speak about how much she meant to him. Miranda was killed in a car crash, Markiplier revealed earlier this week.
"Miranda, when I first started YouTube, was one of my earliest supporters," Markiplier, 28, says in the new video. "Not a fan, just honestly, truly was proud of what I was doing and she would often go to school and brag about the fact that she was related to me."
Miranda's father, Mike, thanked Markiplier's fans for their support.
"Thank you so much for all the prayers. The prayers are probably what have helped me and my wife and the rest of my family get through these last couple days," he said.
Markiplier has also set up a GoFundMe page to help Miranda's family with the funeral expenses. As of Friday morning, the page had raised nearly $75,000 — far surpassing the initial goal of $15,000.
Watch the full message below: