According to The Sun, the Queen had a few things she wanted to discuss with Harry and Meghan ahead of the royal birth.
"Her Majesty wanted to formally welcome the Sussexes to their new home so she was their first visitor," a source told told the publication.
"After all, they've practically moved into her back garden.
"She visited with other family members and Harry and Meghan were delighted to show them around."
It is also believed that the Queen spent time chatting with Meghan's mother, Doria Ragland, who is currently staying with her daughter and son-in-law.
Meanwhile, it was also revealed last week that the Duke and Duchess of Cambridge visited Harry and Meghan following the Easter Service at St George's Chapel despite rumours of a rift.
Royal baby: What do we know so far?
"They took with them, we hear, a housewarming present when they went around for a meeting," Royal correspondent Chris Ship told Today.
"You could call it a 'clear-the-air' meeting in some respects."