HELLO! understands that Prince Harry and Meghan privately congratulated the couple on their new arrival.
Mike and Zara welcomed their son – Lucas Philip Tindall – on Sunday 21 March at their Gatcombe Park home. The couple are already parents to Mia, seven, and two-year-old Lena.
WATCH: Mike Tindall reveals the birth of his baby boy on his podcast
Former rugby player Mike has always had a close relationship with his wife Zara's cousin, with the couple stepping out to support a number of Harry's causes over the years.
As well as attending Harry and Meghan's royal wedding in May 2018, Mike and Zara were spotted in the crowd at the Sentebale Concert in 2016 – a charity which helps vulnerable and HIV positive children of Lesotho and Botswana.
Harry and Mike have been spotted enjoying a laugh during family get-togethers, including the Patron's lunch to celebrate the Queen's 90th birthday in 2016 and polo matches. The pair even competed against one another in a star-studded wheelchair rugby match at the Invictus Games 2014 in London.
William and Harry share a close bond with cousin Zara and husband Mike
The Duke and Duchess of Sussex attended Lena's christening in March 2019 and Zara chose Harry to be one of her daughter's godparents.
Meanwhile, Harry and Zara's cousin, Princess Eugenie, also welcomed a baby boy – August Philip Hawke Brooksbank – with her husband Jack on 9 February.
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