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It’s climb time!

All the world’s a jungle gym to Tobey Maguire‘s 3½-year-old son Otis Tobias, who gets a hand from his doting dad on Thursday while out in L.A.

Also parents to 6-year-old daughter Ruby Sweetheart, The Great Gatsby star and his wife Jennifer Meyer Maguire chose names for their children after they were born — a plan that backfired on the jewelry designer.

“I got an extra form and filled it out and misspelled Otis,” Maguire, 37, told Ellen DeGeneres.

“[I] brought it back to my wife and was acting very innocent. ‘Oh, I’m so excited! It’s official! Look,’ and I handed her the paper.”

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