Prince Harry, Meghan Markle 'video-called' Kate on 40th birthday: Report

Prince Harry and Meghan Markle ensured they gave sister-in-law Kate Middleton a deserving protocol on her 40th birthday.

Royal expert Christopher Anderson says the Sussexes video called the Duchess of Cambridge to wish her well.

“They did a video call," reports Express.co.uk. "They wished her a happy birthday. [It was] very private. Harry and Meghan were not about to post anything the way they did two years ago.”

Unlike previous years when Harry and Meghan displayed "their affection" for Kate, the former senior royals kept it low-key this time.

Christopher added: "This time everything was kept private"

Kate Middleton celebrated her birthday on Jan.9 with a special ode to late mother-in-law Princess Diana, Queen Elizabeth II and Queen Victoria in a series of three birthday photos.