Less than 24 hours after Meghan Markle and Prince Harry announced their intention to step down as senior members of the Royal Family (opens in new tab), it was business as usual on social media as the Royal Family celebrated Kate Middleton's 38th birthday. Even Princess Meghan and Princess Harry joined in the celebration, continuing their habit of commenting on the Royal Family's birthday posts from their @SussexRoyal Instagram handles.

Kensington Palace Instagrammed a new photo of the Duchess of Cambridge off and on. Meghan and Harry commented on it, leaving a personal message for Kate for all to see. This is the first visible activity on Instagram since the Duke and Duchess of Sussex announced yesterday (open in new tab) about their roles.

Kate and Prince William thanked their fans for their congratulations in a post from Kensington Palace. 'Thank you all for all the lovely messages on the Duchess of Cambridge's birthday Photo ? by @MattPorteous," she wrote.

Meghan and Harry added, "Happy Birthday to the Duchess of Cambridge!? ❤️" The emoji is a sweet touch.

The last event Kate and Meghan were alone together was the Wimbledon Ladies Singles Final this summer. There, the Duke and Duchess personally denied tabloid rumors of a feud between the two and tried to show that they are indeed good friends.

Kate supported Meghan throughout her pregnancy with Archie, and after Meghan became a parent, the two became closer friends. A source told ELLE.com in July, "Catherine and Meghan enjoy seeing each other, and becoming mothers has definitely brought them closer together."

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