Jack, who is the son of Sharon and Ozzy Osbourne, said if he could “survive” his family then the couple could survive the royal family.
Meghan and Harry shocked royal watchers and their own family when they announced they would be “stepping back” as senior royals, which they say will involve becoming financially independent and splitting their time between the UK and North America.
And Jack, 34, waded into the debate on Thursday, tweeting: “Listen Prince Harry, if I can survive my family, you can survive yours.”
The tweet left his followers in stitches, with one replying: “Hard to argue with that logic!”
“Now THAT’S funny…and true,” another posted.
A third said: “Ain’t that the truth.”
“OMG TRUE. @KellyOsbourne alone would send me off,” another joked.
Harry and Meghan made the bombshell announcement on Wednesday night.
They said: “After many months of reflection and internal discussions, we have chosen to make a transition this year in starting to carve out a progressive new role within this institution.
“We intend to step back as ‘senior’ members of the Royal Family and work to become financially independent, while continuing to fully support Her Majesty The Queen.
“It is with your encouragement, particularly over the last few years, that we feel prepared to make this adjustment.
“We now plan to balance our time between the United Kingdom and North America, continuing to honour our duty to The Queen, the Commonwealth, and our patronages.”
A statement was released by the Queen’s office shortly after Meghan and Harry posted their news online, warning of “complicated issues”.
It said they understand Meghan and Harry’s “desire to take a different approach”, but warns it will take time to work out the details.
It reads: “Discussions with The Duke and Duchess of Sussex are at an early stage.
“We understand their desire to take a different approach, but these are complicated issues that will take time to work through.”