The retired rugby star, who is a father to Mia, seven, Lena, three, and eight-month-old Lucas, gave a rare insight into his children's relationship with their cousins, Prince George, Princess Charlotte and Prince Louis.
Talking to The Telegraph in 2019, shortly after the birth of the Duke and Duchess of Sussex's first child, Archie, he remarked on Prince Harry as a new father, saying: "He'll be a great dad. Obviously, he's godfather to Lena, but we've got a great group of young ones in the family now.
WATCH: The next generation of young royals
"Lena and obviously Louis are similar ages and Mia's sort of in between Charlotte and George, and then you've got Peter [Phillips'] children Savannah and Isla who are just a little bit older.
"James (Viscount Severn, Prince Edward's son) is, well, not exactly the ring leader, but he's the oldest. So, yeah, it's going to be a good little group."
Meanwhile, Meghan gave birth to a daughter, Lilibet, in June, and Princess Beatrice and Edoardo Mapelli Mozzi celebrated the arrival of baby Sienna in September. The Queen now has 12 great-grandchildren in total.
The Tindalls pictured with Kate and George in 2015
The Tindalls are particularly close to Prince William and Kate, and were pictured together at the Burnham horse trials in Norfolk during the Easter holidays in 2019. Photos showed Kate giving Charlotte a piggyback ride, while William had goddaughter Mia on his shoulders. Mike, meanwhile, balanced George on his.
The pandemic has restricted family gatherings for the royals in the past 21 months.
Mike previously spoke about his hopes for their children forming friendships shortly after the birth of Princess Charlotte in 2015. He told HELLO! at the time "it's great" that a new generation of young royals are springing up.
"They're all quite close in age and hopefully they'll grow up as good friends," he said.
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