Jazmin Grimaldi has celebrated her 'brotherly love' with her younger half-siblings by sharing a series of invisible snaps on Instagram to mark their ninth birthday.
The California-based actress, 31, the 'illegitimate' daughter of Prince Albert of Monaco with Tamara Rotolo, went Instagram to share unseen photos of Prince Jacques and Princess Gabriella.
The message comes after Princess Charlene's decision to delete her Instagram account to protect her children's privacy and keep them away from the 'pressures' of life in the public eye for as long as possible.
However, Jazmin – who has had a string of small film roles – took to social media to share a selection of personal images featuring the kids with her 35,000 followers.
Prince Albert's son Alexandre Grimaldi-Coste – Albert's eldest son with Nicole Coste, 52, a former Air France flight attendant from Togo, was also featured in the birthday post.
Jazmin Grimaldi (pictured center) shared a birthday tribute post for the ninth birthday of Prince Jacques (pictured left) and Princess Gabriella (pictured right)
On Instagram, Jazmin wrote: 'Happy 9th birthday to my brother Jacques and my sister Gabriella! Swipe for more brother-sister love!'
The first image showed an official portrait of the twins that was previously shared on the Monaco Palace Instagram page.
Princess Gabriella wore a chic navy blue coat with a medal on the lapel, and she completed the look with a matching beret.
Her twin brother looked dapper in a military-style uniform blazer paired with navy trousers.
Jazmin then shared a photo of her with the twins on what appears to be a summer day out.
Jacques held a Sonic the hedgehog toy while Gabriella sat next to Jazmin with a smile on her face.
The last photo showed twins Jazmin and Alexandre on a family day out. The siblings smiled for a photo on a bench with their arms around each other.
Princess Gabriella Thérèse Marie and Prince Jacques Honoré Rainier were born by Caesarean section on December 10, 2014 at the Princess Grace Hospital in Monaco.
The American actress shared an unseen photo from a family day out with the twins and Alexandre Grimaldi-Coste (pictured right)
The official portrait shared on the Monaco Palace Instagram page was also among the photos
A trained opera singer, Jazmin is the little-known daughter of Prince Albert II of Monaco and American real estate agent Tamara Rotolo.
A DNA test in May 2006 confirmed that Albert was the father of Jazmin Grace, the result of an affair with Tamara Rotolo, an American real estate agent he met while she was on holiday in the south of France.
Her mother, a waitress at the time, had an affair with the monarch in 1991 while she was on holiday.
Born in Palm Springs and raised in Palm Desert and Orange County, Jazmin had a childhood marked by a striking normality.
She got straight A's at Catholic school, played forward on her high school's basketball team and, like her grandmother, showed an early appetite for the stage, performing with her church choir and in school plays.
However, she did not meet her father until she was 11 and visited Monaco for the first time. It was, she says, a moment that would redefine their relationship forever.
A trained opera singer, Jazmin is the daughter of Prince Albert II of Monaco and American real estate agent Tamara Rotolo
“I wanted to connect with my father at that moment, get to know him and let him get to know me,” Jazmin said in 2015.
'Because I didn't have that figure with me, I missed that. It's great that it happened when it did, and we've had a great relationship ever since.”
Tamara, now a real estate agent, took Jazmin to California and didn't meet her father until she was 11 years old.
In August last year, Jazmin revealed her close relationship with Albert's second love child, Alexandre Grimaldi-Coste, as she marked his 18th birthday in a sweet Instagram post.
She previously shared a series of Instagram posts from her half-brother's birthday party, writing: 'It's a party. Happy birthday, my little brother Alexandre!'
An opera-trained singer, Jazmin sang with a friend's band in college before launching her solo career with a cabaret-style showcase, Fall in Love With Jaz, at the Duplex Theater in Manhattan.
But she is also a frequent visitor to the Prince's Palace of Monaco, her family's historic 235-room fortress on the French Riviera.
Photographer Michael Avedon, whose late grandfather Richard photographed Grace Kelly, shot Jazmin there for her Harper's Bazaar spread, in which she modeled a series of outfits that exuded old Hollywood glamour.