Meghan Markle and Prince Harry may have deliberately snubbed Prince William on his birthday, according to a royal insider.

The Duke of Cambridge celebrated his 37th birthday on Friday. A number of royal fans flooded Kensington Palace’s post on Instagram with warm greetings for the future king. However, the Duke and Duchess of Sussex didn’t seem to put in the same effort to celebrate the event.

Prince Harry and Markle only commented on Kensington’s Post with, "Happy Birthday to the Duke of Cambridge." This was very formal compared to how they greeted the Queen, Prince Philip and even Prince Louis, adding emojis and personal touches like “love lots” and “granny” to their posts.

“I think it’s a snub if they don’t leave one for Prince William as they did for the Duke and for the Queen,” Majesty Magazine editor Ingrid Seward told Fabulous Digital.

“If they don’t I think it’s pretty rude and will certainly be construed as purposeful,” Seward continued, before adding that Prince William is not just a cousin or a friend but Prince Harry’s big brother.

Seward is not the only person who commented on Prince Harry and Markle’s approach to greeting Prince William. Some netizens criticized the Duke and Duchess of Sussex for sending the second-in-line to the throne what they deemed a "cold" and "useless" birthday greeting.

One follower said that it appeared as if they really didn’t want to wish Prince William well on his special day. Another said that it was a confirmation that something unsettling is happening between them, which is very sad.

Earlier this week, there were reports claiming that Prince Harry and Markle hired a social media expert to catch up on Prince William and Kate Middleton’s popularity. The Duke and Duchess of Cambridge remain the most followed royal.

Marke was reportedly “unhappy” that Prince William and Middleton have more followers. She wanted to close the 700,000 followers gap by hiring an expert. Duncan Larcombe said that hiring separate media personnel is a confirmation that there’s truth to the rumors about the fab four’s rift because it suggests that they are now living in a different place.

Also, Prince Harry and Markle have also decided to split their charity from Prince William and Markle. Larcombe found it odd why the new parents have to do it when all of them support the same causes. He stressed that Prince Harry and Markle have changed their mind and no longer want to be under Prince William and Middleton.

Prince William Meghan Markle and Prince Harry
Prince William, Meghan Markle and Prince Harry attend an Anzac Day service at Westminster Abbey on April 25, 2018 in London. Getty Images/Eddie Mulholland