Royal baby: Meghan Markle is saving a special heirloom to pass on to her daughter Lilibet

Meghan purchased the piece when she was starring on Suits

The Duke and Duchess of Sussex have welcomed their second child, Lilibet.

The couple announced the birth of a sister to their son Archie on Sunday. Lilibet Diana Mountatten-Windsor was born in California on Friday morning.

The Duchess of Sussex has been saving a special gift for her daughter for a number of years.

Prior to moving to London and marrying Prince Harry, Markle was a successful Hollywood actress on the television drama Suits.

It was during her days acting as Rachel Zane that Markle splurged on an expensive and timeless gift to herself, a £4,200 Cartier watch - with the hopes that she would one day pass it on to her daughter.

Speaking to Hello! magazine in 2015, Markle said: “I’ve always coveted the Cartier French Tank watch.”

So when the former actress found out that the show had been picked up for a third season, she “totally splurged” and bought a two-tone version of the watch.

Markle even engraved the classic piece with “To M.M. From M.M” - and revealed she plans to “give it to my daughter one day.”

The jewellery is even more sentimental because Markle always knew what she wanted to do with the designer timepiece.

Markle purchased the watch while she was acting on Suits

“That’s what makes pieces special, the connection you have to them,” the Duchess of Sussex told the magazine.

The Cartier Tank was also a favourite of Princess Diana, Prince Harry’s late mother, who owned a Tank Louis Cartier and an all-gold Tank Française, according to the New York Times.

The watch design itself is more than 100 years old, which makes it the perfect piece for a family heirloom.