Giuliana Rancic and Bill Rancic threw a lavish birthday party for their son Duke's first birthday on Sunday.

Life & Style Weekly published a report in their latest issue with photos of the Giuliana and Bill's affair held in Malibu, Calif. on Sunday. The issue provides all of the details that made the event the success that it was.

Baby Duke's birthday party had a Western Cowboy theme. The couple treated their 90 guests, including 35 children, to a three-hour party that included pony rides. The party also offered a petting zoo, cowboy-themed cake, a lemonade stand and face painting. The Fashion Police star told the magazine she couldn't believe his first birthday arrived so quickly.

"It's crazy, but I can't believe it," Giuliana told Life & Style. "It's wild that it's been a year!" 

Giuliana told E! News she chose a Western theme in honor of the late Hollywood actor John Wayne. Wayne's nickname was Duke.

Five weeks ahead of Duke's birthday, she also opened up to Us Weekly about her plans for his birthday. At the time, she said the theme of the event was undecided. The red carpet host said because the baby is half-Italian, she was considering an Italian theme.

"You guys will hear all about it, it will be a blowout!" she said.

The celebrity couple welcomed their son Duke on Aug. 29 in a Denver hospital. Duke, the first child for both parents, was brought to term via a gestational carrier and weighed seven pounds, four ounces and measured 20 inches.

Prior to his birth, Giuliana endured several failed IVF attempts and a miscarriage. She was diagnosed with breast cancer in 2011 and later underwent a double mastectomy.

The couple has several projects in the works. Season 6 of Giuliana & Bill premiered on on E! in June.

Tags: Giuliana Rancic giuliana & bill