The 31-year-old singer wrote:
'We are ecstatic to welcome our new beautiful healthy happy baby girl, Willow Sage Hart. She's gorgeous, just like her daddy [Carey Hart]. #beyondblessed'
The day before, Pink had posted that it was a 'good time' for something new, writing:
'New Moon in Gemini today :) a good time to start something new.... Also called the Honey Moon. #intoit,'
Congratulations to Pink and Carey - and what a cute name!