The singer and podcaster took to Instagram, where she shared photos of her new baby, Rafe, with his older brother Robin, five, and their dad Chris.
Rosie also shared a sweet video which showed Robin and Chris about to take Rafe for a walk in his pushchair.
In the short clip, a clearly excited Robin shouted: "Bye bye stinky bum," to his mum before running back for a kiss. He then shouted "Love you!" as he ran off with his dad and little brother.
WATCH: Chris and Rosie Ramsey's son expresses excitement over baby brother in adorable video
"Look after our Rafe, bye!" Rosie called as her family walked away.
The mum-of-two captioned the images with a heart-melting message which started: "Truth is, I’m recovering from a section. I’m in absolute agony. I’m very short on sleep as Rafe is a nighttime guzzler.
Chris and Rosie are proud parents of two
"BUT I have honestly never felt so happy in my entire life. My heart could physically explode out of my chest."
The sweet caption continued: "Thank you to the powers that be for everything that I have. I feel like the luckiest person in the world right now. [heart emoji]."
The doting mum's followers were quick to empathise with her mix of emotions, with one commenting: "Oh my goodness, I’m feeling emotional watching this. Brings back memories."
Another wrote: "Absolutely beautiful post Rosie," while a third chimed in: "Revel in it, absorb it, this is your time."
The couple welcomed baby Rafe on Wednesday
A fourth commented: "Oh that last picture my ovaries xxx."
Rosie and her husband welcomed little Rafe to their family on Wednesday, after Rosie had a planned C-section.
The couple had previously opened up about experiencing a missed miscarriage, with Chris telling Lorraine Kelly on an episode of her show in 2018:
"The worst bit of the whole thing is Rosie’s body still thought she was pregnant… we talked about whether to go public with it and we thought, 'let’s do it' and we’re so glad we did."
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