Drugs, Meltdowns & More! Bob Saget Reveals The 20 Biggest 'Full House' Secrets

How rude! Bob Saget spilled all the behind-the-scenes dish from his Full House years in his book, Dirty Daddy. From getting high on set to changing Ashley and Mary-Kate Olsen's diapers, only RadarOnline.com has all the details!

How rude! Bob Saget is spilling all the behind-the-scenes dish from his Full House years in his new book, Dirty Daddy. From getting high on set to changing Ashley and Mary-Kate Olsen's diapers, only RadarOnline.com has all the details!

Uptight Danny Tanner would never touch drugs, but Saget claims he took whip-its with co-stars John Stamos and Dave Coulier while filming a birthday episode one year. After locking themselves in the prop room, he writes, "we inhaled the little bit of air still left in the cans that were meant for Michelle's birthday cake scene. I guess we got high. Don't think so though. It was hard to tell… We were laughing, paranoid to be doing something so dumb!"

Speaking of dumb, "One time, I was holding a cup of coffee, and on the cast's cue, I threw it without thinking onto a wall of high-voltage lighting switches," Saget writes. "Luckily no fire started, the coffee mug just fell to the floor, but I was appropriately scolded by producers like a kid in school getting sent to the principal's office."

In another episode, he was caught getting raunchy with the Olsen twins' stand-in. "Ashley and Mary-Kate were in school, so I had to camera-rehearse without any other characters and just the technical crew, with this four-foot-tall rubber doll," he explains. "Only adults were there. … So I'm throwing it around, pretending to do stuff to it, as one would do if there were no child actors within a couple sound stages' distance and you were a comedian with no moral compass in front of a crowd of people … and what I didn't know was the television monitors were on in the schoolroom, and all the dressing rooms, and in certain offices on the studio lot."

He also admits that he "would occasional lose it while we were shooting and arbitrarily yell out things like 'C*Ck! Sh*t! F*ck!'"

His co-stars Coulier and Stamos got in on the subtly dirty jokes too, but "Since then, Ashley has told me that she and her sister knew when everyone was laughing at something inappropriate," Saget reveals, "but they just didn't know what it was."

Saget got up close and personal with the Olsen twins when they were just infants. Saget claims he “actually did change Mary-Kate’s and Ashley’s diapers once. … a coupe times. Cameras were rolling and one of the young ladies had made a poop, which had to be removed or we would have been holding a child with a smashed-poo-filled diaper for a long scene.”

As they grew older, he reveals, "They were more than aware of the "countdown" that people had conjured up that led to the day when they'd both turn eighteen."

One cast member who had trouble acting his age was Coulier, who "would fart. Loudly. On cue," Saget claims. "The set always smelled like his ass. All the show's eight seasons of outtake gag reels have the whole cast leaving the stage abruptly the moment Dave releases his ass fumes. It gave true meaning to the term 'gag reel.'"

For Saget, Stamos, and Coulier, immaturity was catching. "For example, when we would go over the scripts together in a conference room with the producers and writers, we were all supposed to be taking notes ,but I'd be drawing penises on the scripts and showing them to Dave and John like I was in fifth grade," Saget writes. "I couldn't help it.

Even after the show wrapped, they still got up to mischief together. "John and I once went into a bathroom at the Laugh Factory in Hollywood and stood next to each other at the urinals," Saget reveals. "There was another dude in there, a young guy who looked probably around eighteen. So, out of nowhere/on purpose, John and I start to talk in character as Jesse Katsopolis and Danny Tanner from the show … The eighteen-year-old kid couldn't believe it. He peed all over himself. For that instant, the poor kid thought Full House was real."

 In another instance of art imitating life, Coulier and Saget were actually real-life roommates long before they lived under the same roof on Full House. "When Dave first moved out to L.A., he stayed on my couch …" Saget reveals. "More than ironic that thirteen years before the pilot of the show, Dave really did live with me. And he was cast on the show a year before I was."

Speaking of couches, on set, Saget made them his playground. Once a psychologist was visiting the set and "she told me I was having a 'manic episode,'" Saget reveals. "I was running around on set, walking on furniture, without touching the ground, like a little kid does when he pretends he's walking on rocks to keep from fallen in the imaginary river around him. I was just fooling around."

In another memorable episode, he writes, "One time during lunch, I had the kids from the show in a golf cart and I drove right off the lot onto the sidewalk … and started tooling down the street. That's pretty much the whole story. We didn't rob a liquor store or anything noteworthy, but that was my way of doing something a bit rebellious and off-road that broke the day up for the kids."

Saget says he helped shape the way Full House eventually played out. His character, Danny Tanner "had originally been conceived, for the pilot, as a guy who loved his kids more than anything," Saget claims. "But then I worked with the show's producers to embellish him with some other qualities: his being a hugger and a neurotic cleaner…"

In addition, he says, "At first, the show was more about three buddies. That experiment lasted about three episodes. Seemed weird to watch guys trying to hook up and find dates while three little girls were being raised in the house."

As for the San Francisco Victorian pictured in the show's credits, Saget confirms what many fans know: "We never actually filmed anything at the house itself. It's just where the producers put a camera one day for an exterior shot," he writes.

Sometimes, for the sarcastic comedian, playing a lovey dovey dad was hard work for a paycheck. "I never knew my lines or why I was saying them," he writes. "Not totally true. I knew why I was saying them. To put my kids through college.

And after filming, he says, he actively worked to shed his Danny Tanner persona: "I spent twenty years trying to "opposite day" how some people regarded me."

But filming Full House did have its upsides. "One of the most rewarding parts of working on a show like that was hearing from thousands of people who'd lost someone, men who'd lost their wives and had to raise their girls as a single parent," he reveals. "The show hit home for many."

And he also got to witness kiddie co-star Jodie Sweetin's comedy talents long before she spiraled into the addiction she would later describe in her own memoir. "At the start, she was amazing to behold," he writes, "displaying old-school sitcom abilities in the form of a five-year-old.