Ubuntu vs Zorin Grub Menu

I recently installed Ubuntu on a drive that has Zorin on it. As expected, Ubuntu's Grub took precedence. I would boot the computer and Ubuntu's Grub appeared, where I could choose it or Zorin. However, after updating Zorin, I now get the Zorin Grub when booting up. Somehow Zorin took control of Grub, even though Ubuntu was the last OS installed. Any way to fix this?