The growing cycle of Groot is indeed something that will be addressed in Infinity War, by the sound of it.
The motion-capture actor playing (teen) Groot in Avengers: Infinity War has indicated that the character will be coming of age in the film and finding himself a role model.
Of particular interest is how the much-loved walking tree that is Groot will fare upon meeting Steve Rogers, Tony Stark, and the other members of the Avengers.
As with most of the cast interviews for Avengers: Infinity War, it’s also nice to hear Notary refer so positively to the directing Russo brothers and the amount of freedom they’re giving the actors with their performances.