Andrew Mountbatten-Windsor—who lost all of his royal titles and privileges in October in a groundbreaking decision by his older brother, King Charles—has been completely shut out of royal life. His daughters, though, have not, and a royal biographer said that the former Prince Andrew is relying on Princess Beatrice and Princess Eugenie to serve as his “passport” into the royal fold.

Speaking on The Sun’s “Royal Exclusive” show, royal biographer Ingrid Seward discussed Beatrice and Eugenie’s decision to attend Christmas at Sandringham with the royal family—an invitation that their father, the former Duke of York, did not receive as he continues to experience fallout from his association with convicted sex offender Jeffrey Epstein. “I don’t think Beatrice and Eugenie had a choice,” Seward said about whether or not to go to Sandringham. “Andrew said to them, ‘You have to go.’”

“Because he wants to keep a foot in,” she continued. “A, he wants to know what’s going on. B, he’d want to know what people were saying about him. And he’s always said that, and Fergie [Sarah Ferguson, Andrew’s ex-wife] has said, ‘the girls are my passport.’”

She added that Beatrice and Eugenie “are Andrew’s only passport into the royal family now. And I’m absolutely sure that he persuaded them. And they might have said, ‘Oh, Papa, we want to be with you [for Christmas].’ And he’d said, ‘No, I want you to go there. That’s what’s going to make me happy.’”

Royal commentator Charles Rae agreed, saying on the show, “Andrew wants to keep an eye on what’s going on.” He added, “He’s not invited, so he’s not at the table anymore. So one of the first things that would have happened when they got back would be Andrew would be on the phone saying, ‘Right, who said what?’”

Like Andrew, Ferguson has been shut out of royal life, including losing her Duchess of York title and not being invited to Christmas at Sandringham. The former couple—who lived together at Andrew’s 30-room mansion, Royal Lodge, even after their divorce—“live and die by the monarchy, so this didn’t surprise me at all,” a friend told People. Of Beatrice and Eugenie’s decision to attend Christmas at Sandringham, “Andrew and Sarah would have 1,000 percent supported it,” the friend added.

Royal biographer Robert Jobson said of Beatrice and Eugenie’s decision that “They did the right thing—showing loyalty to King Charles and to the Crown. It’s easy to say this is a snub, but they would say, ‘I’m a royal princess, I’m in line to the throne, I have been invited to attend the King’s Christmas celebrations, and you don’t turn down the King’s invitation.’”

“If you have an invitation, you go,” he continued. “It’s not an invitation—it’s a command, really.”