The news was shared by his fiancée, tennis star Maria Sharapova, who shared a photo of herself cradling her newborn alongside Alexander, as they both looked lovingly at their son. "Theodore VII MMXXII. The most beautiful, challenging, and rewarding gift our little family could ask for," the new mum captioned her post. She also added the baby bottle and a chick hatching from an egg emojis.
WATCH: Relive Prince William and Prince Harry delighted royal fans in Windsor
William and Harry are close friends with the pair, with William becoming firm friends with Alexander during their time together in Eton.
Alexander's ex-wife Misha Nonoo is also close friends with the Duchess of Sussex, and reportedly was the person who introduced her to Harry.
Plenty of fans rushed to congratulate Maria and Alexander on the birth of their son, with many sharing messages of jubilation in the comments and heart emojis.
Maria and Alexander welcomed a baby son
The pair have been dating since 2018, and announced their engagement in 2020, and in a sweet post at the time Maria referred to it as their "little secret".
The news came as Prince William had more reason to celebrate after The Earthshot Prize officially became an independent charity.
After founding the hugely successful Prize in 2020, the Duke of Cambridge is set to take on the role of charity President. Backed by a host of celebrities, the Earthshot Prize is a global environmental award designed to foster ground-breaking ecological solutions.
The royal will be joined by four new trustees including M Sanjayan, Jason Knauf, Zoe Ware, and Jean Christophe Gray. Together, the trustees will provide a variety of unique perspectives to help propel the Prize and drive recognition around the world.
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