That'll change in Infinity War, when they start to cross paths with ... against their captor / abuser / surrogate father, Thanos. Groot has gone from a cute baby to a surly teen.

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Then came Teen Groot in Avengers: Infinity War, sulking and ignoring orders like any rebellious adolescent. But when the time came, he stepped up, sacrificing his own branch to complete Stormbreaker.

Diesel voiced Groot for 2014’s Guardians of the Galaxy and reprised the role in 2017’s Guardians of the Galaxy Vol. 2, 2018’s ...