The Groot moviegoers met in Guardians of the Galaxy sacrificed himself near the end of that movie to save his teammates, but from the leftover branches and twigs rose a new Groot. A cuter Groot. Baby Groot. As we've seen from images and the first trailer, Baby Groot will have only slightly grown when we reunite with him in Guardians of the Galaxy Vol. 2, but his small stature won't be the only thing different about him. According to Vin Diesel, he won't be nearly as mentally experienced as his taller self. The actor said:
There is a difference. He couldn't be more naive as baby Groot. I always think of the Groot that we saw in the first Guardians as a college level Groot. He's not fully grown yet, but he's a man. Once he sacrifices himself at the end of the movie, now he has to start all over, so to speak. So we're going to see this goofy, adorable, baby Groot thing running around the screen. Just kinda learning as he goes. I think people are going to love this movie.
While plugging his new movie Billy Lynn's Long Halftime Walk to Collider, Vin Diesel detoured into Guardians of the Galaxy Vol. 2 territory, and noted how in the sequel, Groot will have a significantly more naive mindset compared to how he was as an adult. While it was generally assumed that Baby Groot would behave like a juvenile, Diesel statement confirms that the alien basically be a child, albeit one with extraordinary abilities. However, that mentality doesn't necessarily mean he won't remember what he was like before he was destroyed and regrown. At San Diego Comic-Con, Marvel Studios president Kevin Feige said Baby Groot will retain his memories, although director James Gunn later told a fan that as far as Baby Groot being the original Groot or a "son," that situation is "complicated."
As a side note, Diesel mentioning how we didn't see Groot "fully grown" in Guardians of the Galaxy caught my eye. Does this mean in the future, whether it's later in Guardians of the Galaxy Vol. 2 or Guardians of the Galaxy Vol. 3, moviegoers will see Groot grow even larger? Could he grow as large as one of the gargantuan trees found in the Redwood National Park? Okay, that might be be excessive, but it does beg the question of how large a member of his species can become.
Despite his petite size and childlike mentality, Baby Groot won't be kept away from the intergalactic shenanigans Guardians of the Galaxy Vol. 2 promises to provide. A clip was shown at San Diego Comic-Con of him freeing Rocket and Yondu from imprisonment, though not without some trouble. The young tree alien will also finally have his own wardrobe, as he was shown in the teaser trailer wearing a little leather jacket.
Marvel fans can see Baby Groot in action when Guardians of the Galaxy Vol. 2 arrives in theaters on May 5, 2017.