There's no doubt about it: Groot is one of the standout stars of Guardians of the Galaxy Vol. 2. The tree-like hero has seen significant changes in his appearance and stature over the course of the two movies in the Guardians series so far, and much of that has been thanks to Anthony Francisco, one of the designers at Marvel Studios Visual Development responsible for Groot's new looks.

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Francisco recently shared his early portraits of Groot as a young sapling and an a twiggy teen on his Facebook page.

Alongside his art, Francisco also described the process that led him to find the right designs for young Groot. "One of my favorite contributions to the MCU is the development of Baby Groot," the artist said, adding "I pretty much watched him grow, I did the concept design from potted Groot to Baby Groot, and now Teen Groot! GOTG Vol.2 was all about family and this character is so close to my heart because my kids were the inspiration that helped me in finding the design. And my son is much like baby groot, he is a handful but always cute and adorable :)"

Francisco also detailed some of the feedback he received from the film's director James Gunn. According to the artist, the piece below is "one of my initial designs that James Gunn liked. But Baby Groot just had to be much much smaller! :) It was great to have a clear direction with just our first pass. James Gunn was pretty specific with giving notes and that made the process really smooth."

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Of course, there were also a lot of learning along the way as Francisco worked to get baby Groot looking even more like a toddler in the gallery below.

[vn_gallery name="Artist Anthony Francisco’ Concept Art for Baby, Teenage Groot" id="1079280"]

Those who like Anthony Francisco's GotG work should also check out the Marvel's Guardians of the Galaxy Vol. 2: The Art of the Movie art book, in which the baby and teenage Groot illustrations appear.

Currently screening in theaters, Guardians of the Galaxy Vol. 2 stars Chris Pratt as Star-Lord, Zoe Saldana as Gamora, Dave Bautista as Drax the Destroyer, Vin Diesel as Baby Groot, Bradley Cooper as Rocket Raccoon, Michael Rooker as Yondu Udonta, Karen Gillan as Nebula, Pom Klementieff as Mantis, Elizabeth Debicki as Ayesha, Chris Sullivan as Taserface, Sean Gunn as Kraglin, Glenn Close as Irani Rael and Kurt Russell as Ego.