It’s been a rough offseason for Rob Gronkowski, but it was all positive yesterday for the Patriots tight end. Gronkowski continued his support for One Mission’s fourth annual “Kid’s Cancer Buzz-Off” at Gillette Stadium, where he shaved his head before turning the electric razor on others as 867 men, women and children raised money and awareness for the fight against pediatric cancer. Gronkowski has taken part in the event for the last two years, and his presence has caused the Buzz-Off to boom in popularity. “It’s great,” Gronkowski said. “That’s why I came back this year because last year, the outcome was great. The turnout was great. When the turnout is great, the outcome is great, you want to be part of something and stay part of something while you’re here. It’s excellent, and I’m going to keep my name on this, for sure. It’s a great cause. The kids are running around buzzing off their hair for their friends, family members buzzing off their hair for friends. It’s great to be part of it, and I always would love to put my name on it for this event.” One Mission has raised about $1 million in its first three years, and it hopes to generate another $1 million this year. The Buzz-Off benefited Children’s Hospital Boston. “I had a blast last year,” Gronkowski said. “I came back this year and couldn’t ask for a better outcome, about double the amount of people (from last year’s event). We have 867 kids buzzing off their hair today, and that’s unbelievable. They raised about right around $1 million for (the fight against) cancer for kids, so you can’t ask for a better situation, a better outcome than that. Every single year, it’s growing so far, and we’re having a blast. Everyone here is having a blast, so it’s going good so far.”