Entertainment Tonight ET Online ETOnline.com

After welcoming their son Duke in August, Bill and Giuliana Rancic say they are loving parenthood and already thinking about having a second child.

Speaking Wednesday to the Today show's Kathie Lee Gifford and & Hoda Kotb, Giuliana reported that their son -- who was born via surrogate -- is doing "amazing." When Hoda speculated that a sibling for Duke is probably not the first thing on the couple's mind at this time, Giuliana responded with, "It's the first thing on my mind!"

RELATED: It's A Boy For Giuliana & Bill!

Giuliana said Bill told her that before they have another baby, the couple will first relocate full-time to Chicago, where they have family roots.

The E! News host also talked about the instant connection she felt with her son. "I had gone 37 years without a baby -- you know just focusing on myself and my husband and my career -- I didn't know how I would react when I had him in my arms. And it came so naturally."

RELATED: Giuliana Rancic: Double Mastectomy Was 'Hell'

For his part, Bill said that being a father has been "spectacular" so far. "It puts things in perspective. I think you stop keeping score about the little things in life and you think, wow, this is what life's about. It brings the volume down on things that don't matter." 

The couple also talked about the decision to show their son on their Style network reality show Giuliana & Bill, saying it made sense to show viewers a happy ending after Giuliana struggled so long with infertility and went through breast cancer. But they said that going forward, they plan to be very controlled about exposing Duke to the limelight saying, "he's not going to live that kind of a life."

VIDEO: Giuliana Regrets Chasing Career Over Chasing Guys