“He’s all about spooky stories, taking sticks from the park and turning them into stuff,” explained Duhamel, 44. “We literally have a pile of sticks at our house. We could have a giant bonfire at any moment.”
Adds the actor, “He collects sticks, and to him, they’re something. He doesn’t want to go anywhere without them because they’re either a sword or a magic wand.”
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Of Axl – the couple’s only child – Duhamel insists, “He’s all boy, man, he is all boy,” noting that the toddler’s threes have been a little more challenging than the notorious “terrible twos.”
“I saw a T-shirt the other day. It was for kids, and it said, ‘Terrible twos? I’m having a great time,’ ” recalls the star. “And that’s kind of it: They don’t know that they’re terrible. They’re just having a blast.”
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Duhamel admits that he’s still learning when it comes to parenthood, telling DeGeneres, “I have no idea what I’m doing half the time.”
Luckily Fergie, 42, has it all figured out. “She’s definitely more evolved than I am, and more patient,” says Duhamel about his wife of eight years.
“But I feel like I’m much more – you know, having a kid when I was 40 years old is much different than having one at 22, so I’m a little bit more mature than I was then,” he adds.
Duhamel previously told PEOPLE that he and the singer’s home is the perfect place for their son to explore the outdoors.
“We have this great spot behind our house with all these trails, so he’ll go exploring and gathering things – whether it’s flowers or rocks,” explained Duhamel of Axl earlier this year.
“He really has a fascination with sticks,” continued the actor at the time. “He’s just like me – he loves to be out there, he loves to get outside.”