First photo of newest royal baby revealed weeks after birth: 'Welcome to the world'

A new royal baby has come into the world and royal watchers have just been treated to the first photo of the darling new addition to the Hanover and Monaco royal families.

Prince Christian of Hanover, 38, and wife Princess Alessandra, 35, welcomed their third child in February but kept details quiet.

Now Alessandra, a model originally from Peru, has shared the very first photo of her newborn with the prince on Instagram.

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"Welcome to the world Alexia. Three weeks ago you came to complete our family. We love you infinitely," she captioned a photo of the bub's tiny hand.

Marie-Chantal, Crown Princess of Greece, was among the first to comment on the post, writing "Congratulations!" alongside a slew of heart emojis.

The couple wed in 2017, first in a civil service in London, followed by a lavish ceremony at the San Pedro Church in Lima, Peru.

A number of big name royals were in attendance, including Britain's Princess Beatrice and Princess Eugenie, Greece's Crown Prince Pavlos, Princess Maria Olympia, and Princess Philipos, and several members of the Monegasque royal family.

Other high profile guests also attended, including legendary model Kate Moss.

Alessandra wore a lace wedding gown designed by Jorge Vázquez, with a long veil and the Hanoverian Floral Tiara atop her head.

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They welcomed their first children, twins Nicolas and Sofia, in 2020.

Prince Christian is the second son of Prince Ernst August of Hanover and his first wife, Chantal Hochuli, an heiress to a Swiss chocolate company.

His parents divorced in 1997, when Christian was just 12, and Prince Ernst went on to marry Princess Caroline of Monaco in 1999.

Princess Caroline is the eldest child of Rainier III, Prince of Monaco, and Grace Kelly. Her brother is reigning Prince Albert II of Monaco.

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Caroline and Ernst had one child, princess Alexandra of Hanover, born in 1999 and it's understood the princess is close with her stepsons, Prince Christian and his elder brother.

The pair have been estranged for years after separating in 2009, however they are still married as they never formally divorced.

As such, Alexia is Princess Caroline's grandchild by marriage.