He's a pig success: Illustrator Ian Falconer dazzles children with his best-selling books starring Olivia the pig.

"I was trying to get the book Finished while I was doped up on ets," laughs Ian Falconer, who juggled intestinal surgery and myriad other projects while completing Olivia ... and the Missing Toy (Simon & Schuster, $16.95).

As any child could tell you, Olivia herself would have met the challenge unfazed. A self-possessed little pig who generally "just does the most contrary thing possible," Olivia is one of the most acclaimed new characters in children's literature and the star of Falconer's three number 1 best-selling picture books.

A star himself among illustrators, Falconer published Olivia in 2000 and shot fight by the dreaded sophomore slump with 2001's hit Olivia Saves the Circus. "This one was more scary," though, admits the 43-year-old artist. After all, Falconer has seen Olivia blossom from a gift for a relative into a publishing phenomenon with 2 million copies in print, not to mention related toys like Olivia dolls and paint sets.

After three years of working feverishly, Falconer finally had to take a rest--whether he liked it or not--thanks to an abscessed colon that required an operation. "I was supposed to go to Moscow to do Sleeping Beauty at the Bolshoi," he says regretfully. "But I canceled. I was invited by [director] Joe Mantello to do the sets for the musical Wicked. But I just decided I can't do it. It's almost like lids happened because I've been working so much it forced me to stop."

Chatting in his apartment in lower Manhattan, Falconer is quiet and a little shy, apologizing for not being a better interview and revealing that he never does readings, just signings.

"Children are so honest and direct," says Falconer. "I was doing a book signing just a couple of weeks ago. A little girl was looking at my picture on the dust jacket and said, 'Was this picture taken a long, long time ago?' 'Yes, why?' 'Because you look a lot younger [in the photo].'"

Unlike children's book authors of previous generations, Falconer has always been out. He knew he was gay, or at least, appreciative of men, right from the start "One of my earliest memories is_ being in the locker room at the yacht club," says Falconer. "I was probably only 5 or 6 years old. I was looking around at all the naked men and thinking, Wow!"

But when the biggest names in kids' literature reached out to the latest star, Falconer became shy again. "I was thrilled Maurice [Sendak] left me a message saying he loved the [first] book. So did Hilary Knight [illustrator of the famed Eloise books]," says Falconer, who is single. "I was so intimidated by them at that moment--it was when the books first came out. And I was too shy about celebrities to call them back. But Maurice left me this message that said, 'Hi, Ian. It's, uh ... Maurice Sendak. Um, I'm in the country right now. You can call me back here. You can leave me a message on my answering machine. If I'm not here, I'll probably be out in the garden or, um, slitting my wrists or something. He s very dark and funny.

Falconer plans to do one more book--Olivia Does Christmas--and then walk away. "I think four books would make a nice boxed set." says Falconer. That's his plan, but don't be surprised if Olivia decides otherwise.