According to an insider, Prince William is "extremely concerned" about the Duke and Duchess of Sussex.
The 37-year-old royal and his younger sibling are said to have "grown apart" since the Duke and Duchess tied the knot in May 2018 - but Prince William remains determined to support his brother through the tough times in his life.
The insider told Us Weekly: "William is extremely concerned about Harry and Meghan.
"Even though the brothers have grown apart, William still cares about Harry and is hoping that he'll open up to him about his current struggles.
"William wants to be there for Harry and hates seeing him in such a bad place. Despite their differences, blood is thicker than water."
Prince Charles is also said to be similarly worried about his youngest son.
The source explained: "Harry's a very sensitive guy, and Charles is worried, too. This is a time when Harry needs his family the most."
Meanwhile, Prince Harry recently confessed that he and his brother have "good days and bad days".
The 35-year-old royal - who has a five-month-old son called Archie with his wife - played down rumours of a rift between the siblings, insisting they will "always be there" for each other.
He shared: "We are brothers. We will always be brothers. We are certainly on different paths at the moment but I will always be there for him as I know he will always be there for me.
"We don't see each other as much as we used to because we are so busy but I love him dearly. The majority of the stuff is created out of nothing but as brothers, you know, you have good days, you have bad days."