They welcomed their baby son ‘Little AC’ into the world on Monday.

And just one day later, proud parents Billi Mucklow and her fiancé Andy Carroll could not hide their delight as left hospital with their little bundle of joy.

The former TOWIE star shared a beautiful Instagram snap of her footballer beau, 26, as she followed him while he carried their newborn child down a corridor.

Scroll down for video

'Big AC and Little AC': Billi Mucklow shared sweet Instagram snap of her fiance Andy Carroll carrying newborn baby as they head home following the birth

‘Home Time Big AC and Little AC @andytcarroll,’ she simply captioned the image.

Announcing the birth on their respective social media accounts earlier this week, new mum Billi tweeted: 'Welcome To The World Our Beautiful Baby Boy @AndyTCarroll.'

Father-of-three Andy, 26, posted a photo of the happy family on Instagram, gushing: 'Welcome To The World Little AC!! 9 Months Of Cooking And What A Wonderful Job You Have Done @billimucklow.'

Former The Only Way Is Essex star Billi, 26, and Andy started dating in summer 2013, but didn't go public as a couple until February 2014.

Baby joy: The proud parents cuddle their new baby boy following his birth on Monday in a candid Instagram shot

Andy and Billi got engaged last November after he whisked her off to Rome for a surprise birthday weekend.

In one image posted to her Instagram account, the former TOWIE showed off her sparking engagement ring while standing in front of the Colosseum with Andy.

Captioning the shot, she announced: 'Last night the Love Of My Life Asked Me To Marry Him - I'm So Happy. You Are My Everything and I Can't Wait To Be Your Wife! #MrsCarroll.'

Billi broke the news of her pregnancy on Christmas Day by donning a festive jumper with the words 'making my little pudding' in an Instagram snap with West Ham United footballer Andy, who posted the picture : 'Merry Christmas #OurLittlePudding.'

The blonde left TOWIE in 2013 to focus on her Bikram yoga studio, her second business after running Beaus & Belles beauty salon.

Ready to pop! A heavily-pregnant Billi and Andy having a BBQ a week ago

Countdown is on: Billi and Andy buying a pram for their son a week ago

During her six series on TOWIE, Billi was involved in some high-profile storylines, including a short romance with co-star Tom Kilbey - brother of her best friend Cara.

While their new baby is the first child for Billi, it's the third for Andy, who has a daughter Emilie Rose, five, and son Lucas, three, from a previous relationship.

Andy was previously engaged to Stacey Miller, who he dated from 2011 until 2013.

He was also engaged to Faye Johnstone, who he split from in 2010 when she was pregnant with their second child Lucas.

High-profile: The England International is on £80,000-a-week at West Ham United

Shortly after the pair got together, Billi told The Sun: 'People have got the wrong idea about Andy and it does annoy me because it is just such bulls***.

'He might have made mistakes in the past but he is one of the most caring people I have ever met', she said.

The blonde beauty, who met Andy through mutual friends, says the pair aren't bothered about others peoples opinions.

Billi added: 'Trust is very important to me in a relationship and I trust that he won't ever do me wrong or hurt me.'