Having Superman as an uncle isn’t as great as you might imagine.

The 30-year-old star of the Man Of Steel revealed his seven-year-old nephew has got into trouble for having a super hero in the family – after he was accused of lying at school.

Henry shared an endearing anecdote about little Thomas in an interview with Jay Leno on The Tonight Show, on Thursday.

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Super uncle: Henry Cavill shared an endearing anecdote about his nephew on The Tonight Show With Jay Leno, on Thursday

The Tudors star was dressed in leather boots and a dark blue suit as he chatted with the silver haired talk show host.

Henry was clearly a doting uncle as he relayed a charming story about when his nephew first learned that he would be playing Superman in Zack Snyder’s upcoming reboot.

The actor said: ‘My nephew Thomas was so super excited… he ran to school.’

Supportive family: The 30-year-old actor said his brother Charlie thought that his casting as Superman was ‘awesome’

Charmer: Henry was clearly a doting uncle as he relayed a charming story about when his nephew first learned that he would be playing Superman

Adding a disclaimer before continuing the anecdote, Henry explained: ‘Now keep in mind Thomas has got a great reputation for telling stories and just making up stuff to the teacher [at school].’

The Immortals star continued: ‘So he goes to school dressed in a Superman outfit, because you know he’s all pumped, because his uncle is Superman.

‘And the teacher says, “Thomas why are you wearing this? You’re not supposed to wear this to school.”‘

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Henry went on to convey his nephew’s reply: ‘He says, “Well, because my uncle is Superman,” and she’s [the teacher] like, “Oh okay,” and she pulls him aside… he got in trouble.’

To which the 63-year-old comic legend said: ‘[She was like] “this is sad.”‘

But the onscreen superhero seemed to enjoy the outcome of the tale when his sister-in-law arrived and explained that the boy’s uncle ‘actually kind of is’ Superman.

Star performance: Zooey Deschanel was the musical guest for the Tonight Show episode with her group She & Him

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Meanwhile, Cavill revealed in the new issue of Details magazine how he first met Man Of Steel co-star Russell Crowe, who plays his biological father, Jor-El, in the film, while he was at boarding school.

‘He was on campus filming Proof of Life…Everyone was standing in a semicircle, and I thought, “We look ridiculous, staring like he’s some kind of prize pony.”

‘So I walked up and said, ‘Hi, my name is Henry. I’m thinking of becoming an actor. What’s the acting world like?’ He said something like, ‘Sometimes it’s great. Sometimes it’s not so great. It’s fun acting. And they pay well.’ Then everyone ran up and asked for autographs, and I turned to Russell and said, “Run.”‘

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Crowe later sent him a package with snacks, a rugby jersey, and a CD of the actor’s band with a note that read: ‘”Dear Henry, a journey of a thousand miles begins with a single step.'”

Cavill reminded Crowe of their first encounter while on set of the movie, saying: ‘I told him, “I was the fat one who didn’t ask for your autograph.” He looked at me blankly, and then he actually remembered.’

Man of Steel is released in the US and UK on June 14.

Now that’s what you call eye candy: Henry looks extremely hunky as caped crusader Clark Kent in Man Of Steel