The Black Sabbath rocker and wife Sharon Osbourne are grandparents to Jack's daughters Pearl, 11, Andy Rose, seven, Minnie Theodora, five and Maple Artemis, 14 months, and Kelly Osbourne's nine-month-old son Sidney.
Jack told Fox News Digital of his parents babysitting his daughters: "They won't do it at my house. It's a little easier for them if we drop the girls with them. The good thing is – outside of the baby – it's that they can handle it now, you know, they're much easier. The kids can tell you what they need when they need it."
But he revealed that when it comes to changing nappies, "My dad is like, ‘Hell, no. Like, no.' Because my dad's in that era where, like, men don't touch diapers. Like, that's not that's not what dads do."
And 74-year-old heavy metal star has another strict rule when it comes to his grandchildren.
Jack said: "It's funny. If my kids are at the house and like they all want to get into bed and watch TV with my mom, my dad is like, ‘Nope.’ And he like, gets out of the bed and like, goes. He's like, 'No, I'm not doing that.'"
"I'm like, ‘Why?’ He's like, 'I don't want them going to school being like, 'I was in bed with my grandpa.' He's like, ‘No, not dealing with it.’ And I'm like, ‘OK.’ I'm like, 'Fine, that's your boundary. That's your boundary.'"
But the Paranoid singer continues to spend time playing with his grandchildren, as revealed on wife Sharon's Instagram account.
Ozzy announced his retirement from touring at the beginning of 2023, cancelling the European leg of his No More Tours 2 tour as he told fans he was too unwell to travel from city to city to perform.
But he since said he is eager to perform live again.
He said: "I’ve come to the point where Sharon says to me, 'You know what, the truth of the matter is, you can't keep booking tours and failing, cancelling."
He added: "The only thing I've got that keeps me going is making records.
"But I can't do that forever.
"I gotta get out there."
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