Sometime in February 2018, William unfortunately left Killer Kid due to personal reasons. He said he might come back to the series when everything in his personal life is out of the way. Below is a message from William about his departure from Killer Kid:

"Hello fans of Killer Kid. It's me, William. For a while now, ever since September 2017. I have been feeling down and recently it has gotten worse. I'm sorry but I'm afraid I will have to leave Killer Kid until further notice. Don't worry people, there will be a day where I will do one last Killer Kid video.I started the series with Thomas 3 years ago and we were hoping to end it this year. You see, both of us have our problems and we can't let them interfere with Killer Kid. So I decided to halt the series for a brief period until I move out, have a holiday and a break from life in England. And for the first time in 8 years, feel happy. You will see me on Killer Kid sometime in mid July-August. I apologize sincerely for this news."