Peck reveals his son, Max, was playing with Stamos' kid Billie when he got a call explaining the boys had got into an altercation.
"John was like, 'Let me make it up to you; let's go to Universal Studios. We'll take the boys. It'll be a fabulous time,' " Peck recalls.
He jumped at the opportunity because he thought someone as famous as Stamos would be able to shut the park down for the day.
"I'm thinking, 'I've never been to Universal Studios when it's closed! He [Stamos] doesn't go with the public,' " Josh explains. "I show up and he's in a hat and a mask; he's in full disguise. He's like, 'Let's go and have a great time!' I'm like, 'With the people? You're John Stamos!' "
John himself had shared details of the biting incident in a past interview with Extra. "We were doing an episode of 'Fuller House', and I have a friend, Josh Peck, on [the episode]," he recalled. "His wife brings his son [10-month-old Max Milo] and my wife brings [17-month-old] Billy, who's never done a bad thing in his life."
"They were taking a picture and [Billy] leans over and bites Max [on the face]," the 57-year-old actor continued recounting. "It was horrifying! It was the first time I was disappointed in my son. It was a weird feeling."