Ryan Seacrest, Joan Rivers Congratulate New Parents Giuliana and Bill Rancic

Bill Rancic and Giuliana Rancic attend the 10th Annual Smile Gala on September 23, 2011 in Beverly Hills, California.  Tibrina Hobson/WireImage.com

As Bill and Giuliana Rancic celebrate the arrival of their healthy baby boy, Edward Duke Rancic, their A-list pals are coming out in full force to offer their best wishes to the family.

"Congrats you two! See you in 18 years," Giuliana's E! News cohost, Ryan Seacrest, tweeted Thursday, less than 24 hours after baby Edward was born via gestational surrogate in Denver.

Seacrest's kind words weren't the only ones from Giuliana's E! family. "THRILLED for Giuliana Rancic and Bill Rancic on the birth of their baby boy! She is my extended family and I can't be more excited for them!" Fashion Police's Joan Rivers tweeted. Asked Kelly Osbourne: "When can I see Duke?"

ryan seacrest and joan rivers
Ryan Seacrest and Joan Rivers Michael Kovac/Getty; Michael N. Todaro/FilmMagic

Both present in the delivery room during their surrogate's four-hour labor, Bill, 41, and Giuliana, 37, are already over-the-moon about their new arrival. "Bill and I are blessed beyond words to welcome Edward into our lives," Giuliana said after officially becoming a first-time mom. "We are so in love with the little guy already!"

Announcing that they were expecting in April, the couple of five years can't say enough about the woman who carried their son to term. "She's great. She's a very caring woman," Bill tells Us Weekly of their surrogate.

As for his son, Bill credits the baby with saving his wife's life. "Technically this baby saved her life because had she not gone through IVF — the doctor made it mandatory that she get a mammogram — they would have never found what they found so we owe this little guy debt of gratitude and I'm sure he'll never let you forget it!"

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