Hugh Hefner’s son Cooper welcomes daughter Betsy Rose with his wife Scarlett Byrne

Hugh Hefner’s son Cooper has officially become a father after welcoming his first child with actress wife Scarlett Byrne – a baby girl named Betsy Rose after the new dad’s late grandmother. 

The 28-year-old California Senate hopeful shared the joyful news of the couple’s new arrival on Instagram, posting several images of their adorable family-of-three while gushing to his followers: ‘We are overwhelmed with gratitude, love, and joy!’

Cooper and Scarlett’s newborn weighed 6lbs 5oz, and the couple revealed that they named her in honor of the new dad’s late maternal grandmother, Betsy Aldridge Conrad, who passed away just last month.   

Congrats! Hugh Hefner’s son Cooper and his British actress wife Scarlett Byrne welcomed their first child – a daughter named Betsy Rose – on Monday at 5:23pm in Los Angeles

Overjoyed: The 28-year-old politician - who boasts 265,000 social media followers - gushed in his official birth announcement: 'We are overwhelmed with gratitude, love, and joy!'

Overjoyed: The 28-year-old politician – who boasts 265,000 social media followers – gushed in his official birth announcement: ‘We are overwhelmed with gratitude, love, and joy!’

‘My grandmother meant the world to both Scarlett and I,’ Hefner told E! News while speaking about the couple’s choice of name for their baby girl. 

‘Scarlett and I are filled with such joy. We couldn’t be happier… We look forward to being home and spending time together as a family in the days and weeks ahead.’

In a touching photo shared by the proud father, Hefner is seen standing alongside his wife, who is lying in a hospital bed and cradling their newborn bundle of joy. A video posted alongside the images shows mom and dad sharing a sweet kiss while cuddling their baby girl. 

The arrival of baby Betsy was no doubt a bittersweet milestone for the former Playboy CCO, whose famous father Hugh passed away, at age 91, in 2017 from sepsis brought on by an E. coli infection. 

Hefner is the son of Hugh and his second wife, former Playmate of the Year Kimberly Conrad, whom he married in 1989, before the couple officially divorced in 2010 after separating in 1998.  

'My grandmother meant the world to us': Cooper named his newborn baby - weighing in at 6lbs, 5oz - in honor of his grandmother Betsy Aldridge-Conrad, who passed away last month

‘My grandmother meant the world to us’: Cooper named his newborn baby – weighing in at 6lbs, 5oz – in honor of his grandmother Betsy Aldridge-Conrad, who passed away last month

Hefner told E! News: 'Scarlett and I are filled with such joy. We couldn't be happier...We look forward to being home and spending time together as a family in the days and weeks ahead'

Hefner told E! News: ‘Scarlett and I are filled with such joy. We couldn’t be happier…We look forward to being home and spending time together as a family in the days and weeks ahead’

RIP: It's a bittersweet milestone for the former Playboy CCO, whose famous father Hugh Hefner passed away, at age 91, in 2017 from sepsis (pictured in 2016)

RIP: It’s a bittersweet milestone for the former Playboy CCO, whose famous father Hugh Hefner passed away, at age 91, in 2017 from sepsis (pictured in 2016)

Betsy is named for Conrad’s mother, who passed away less than a month ago, Hefner revealed in a touching Instagram tribute, describing her as ‘another mother’. 

‘She was a mother, grandmother, sister, friend, and loved one,’ he wrote in the July 16 tribute. 

‘For the grandchildren of our family she was our Mema. Mema was kindhearted, generous, and loving to all who knew and met her. Each of our lives more wonderful as a result of being blessed with her soul and spirit. 

‘For me, Mema was another mother. The two of us shared a bond that filled my life with a joy and warmth that took me home no matter where I was in the world. How lucky we are to have been beneficiaries of her love. How lucky we are to carry her in our hearts each day moving forward. 

‘Until we see you again, we love you, with all our hearts, our Mema, my Mema.’ 

The late Playboy founder’s ex-girlfriend Kendra Wilkinson – who lived with him from 2004-2009 – commented on Cooper’s post: ‘Congrats to you all. She’s beautiful. Welcome to the world Betsy!’

Luckily, Hefner’s privileged princess has grandmother Kimberley Conrad, who divorced Hugh in 2010 after nine years of marriage.

Scarlett – who’s known for her roles in Hulu’s Runaways and the Harry Potter franchise – hosted a virtual baby shower on July 11 via Zoom.

The late Playboy founder's ex-girlfriend Kendra Wilkinson - who lived with him from 2004-2009 - commented: 'Congrats to you all. She's beautiful. Welcome to the world Betsy!'

The late Playboy founder’s ex-girlfriend Kendra Wilkinson – who lived with him from 2004-2009 – commented: ‘Congrats to you all. She’s beautiful. Welcome to the world Betsy!’

Sneak peek of nursery! Luckily, Hefner's privileged princess has grandmother Kimberley Conrad, who divorced Hugh in 2010 after nine years of marriage (pictured July 2)

Sneak peek of nursery! Luckily, Hefner’s privileged princess has grandmother Kimberley Conrad, who divorced Hugh in 2010 after nine years of marriage (pictured July 2)

'Our baby is already so loved by a wonderful community!' Scarlett - who's known for her roles in Runaways and the Harry Potter franchise - hosted a virtual baby shower on July 11 via Zoom

‘Our baby is already so loved by a wonderful community!’ Scarlett – who’s known for her roles in Runaways and the Harry Potter franchise – hosted a virtual baby shower on July 11 via Zoom

The Chapman University professor legally married the British 29-year-old on November 4 in a civil ceremony in Los Angeles after a four-year engagement.

A month later, Cooper officially enlisted in the US Air Force as a Reservist and completed basic training at Lackland Air Force base in San Antonio, Texas.

Hefner announced July 13 that he’s launching an exploratory campaign to run as a Democrat for the California Senate in the state’s 30th District, which includes Los Angeles County.

In bloom: The Chapman University professor legally married the British 29-year-old on November 4 in a civil ceremony in Los Angeles after a four-year engagement (pictured July 11)

In bloom: The Chapman University professor legally married the British 29-year-old on November 4 in a civil ceremony in Los Angeles after a four-year engagement (pictured July 11)

Serving his country: A month later, Cooper officially enlisted in the US Air Force as a Reservist and completed basic training at Lackland Air Force base in San Antonio (pictured February 18)

Serving his country: A month later, Cooper officially enlisted in the US Air Force as a Reservist and completed basic training at Lackland Air Force base in San Antonio (pictured February 18)

Political aspirations: Hefner announced July 13 that he's launching an exploratory campaign to run as a Democrat for the California Senate in the state's 30th District, which includes Los Angeles County

Political aspirations: Hefner announced July 13 that he’s launching an exploratory campaign to run as a Democrat for the California Senate in the state’s 30th District, which includes Los Angeles County