Stars react to Prince William and Kate's baby news

Prince William and his wife, Kate, Duchess of Cambridge, walk together during the opening of the Football Association's National Fooball Center at St. George's Park in Burton upon Trent, England. / ADRIAN DENNIS/AFP/Getty Images

Prince William and Kate announced Monday that they're going to be parents, and reactions have begun pouring in.

Kate Middleton, #Kate and #royalbaby quickly became top trends on Twitter after St. James' Palace revealed news of the Duchess of Cambridge's pregnancy, and well-wishes have since come from celebrities and even Britain's prime minister.

Here's what some of them had to say:

PM: "I'm delighted by the news that the Duke & Duchess of Cambridge are expecting a baby. They will make wonderful parents." #royalbaby
-- UK Prime Minister (@Number10gov) December 3, 2012

Congratulations to the Duke and Duchess of Cambridge!! A royal baby!!! :) awwww so sweet
-- Khlo?KardashianOdom (@KhloeKardashian) December 3, 2012

Awww so cute! Congrats!!! RT @khloekardashian: Congratulations to the Duke and Duchess of Cambridge!! A royal baby!!! :) awwww so sweet
-- Kim Kardashian (@KimKardashian) December 3, 2012

Congratulations to every magazine editor for calling Kate Middleton's pregnancy - especially those who did covers on it 11 months ago.
-- Piers Morgan (@piersmorgan) December 3, 2012

A ROYAL BABY
-- Brooklyn Decker (@BrooklynDecker) December 3, 2012

I'm sooooooo excited that we're having a royal baby !!!! Congratulations to Kate and Wills !!!!!!
-- Cheryl Cole (@CherylCole) December 3, 2012

A royal baby is on the way for #KateMiddleton and Prince William! lovely! #royalbaby
-- Ivanka Trump (@IvankaTrump) December 3, 2012

Wonderful news for Prince William & Kate Middleton. Kate has Hyperemesis. Had that with my last child. Not fun at all. Hang in there, Kate.
-- Maria Shriver (@mariashriver) December 3, 2012

Congrats to Kate & Will on expecting your first child. The happiest day of your life to look forward to!
-- richardbranson (@richardbranson) December 3, 2012