Chris Hemsworth doesn't understand how his twin sons can be so different.
The Australian actor - who has kids India, six, and twins Tristan and Sasha, four, with his wife Elsa Pataky - has admitted he's still struggling to come to terms with the contrasting personalities of his sons.
He confessed: "I don't get how I can teach them the same thing but they be so different?
"Tristan is so athletic but there's not an aggressive bone in his body. He's the most emotional one. Whereas Sasha is like a little gangster. The other day, we were in the park and something happened with Tristan and another kid. He comes over in tears.
"I'm like, 'What's wrong?' but he didn't want to tell me. Sasha's like, 'Tristan, what happened?' They're four, by the way. 'Another kid pushed me.' Sasha goes over to this older kid, taps him on the shoulder and says, 'Why'd you push my brother?' I'm stood there thinking, I should step in, but this is awesome."
Chris, 35 - who is perhaps best-known for playing Thor in the Marvel movies - is one of Hollywood's most sought-after stars.
But the actor admits that one of the best aspects of his job is that, unlike a director, he never has to commit too much of his time to a particular project.
Speaking to GQ Australia, the 'Avengers: Infinity War' star explained: "Over the years, I've gotten more confident with my own voice. I've realised my strengths are in doctoring things - sorting through the chaos and reassembling the puzzle - stealing everyone else's ideas and taking credit for it.
"What I love about acting is the in-and-out nature of it. Whereas with directing you have to commit a minimum of two years, really. You need to be as enthusiastic about it on day one as you are at day 800. I wonder if I could maintain that stamina."