It's definitely grown.
( It ( ( ( 's definitely ) grown ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ 's) (ADVP (RB definitely)) (VP (VBN grown))) (. .)))
I thought it was gonna grow bigger, but it looks like it's smaller.
( ( ( ( ( I ( thought ( it ( was ( gon ( na ( grow bigger ) ) ) ) ) ) ) , ) but ) ( it ( looks ( like ( it ( 's smaller ) ) ) ) ) ) . )
(ROOT (S (S (NP (PRP I)) (VP (VBD thought) (SBAR (S (NP (PRP it)) (VP (VBD was) (VP (VBG gon) (S (VP (TO na) (VP (VB grow) (NP (JJR bigger))))))))))) (, ,) (CC but) (S (NP (PRP it)) (VP (VBZ looks) (SBAR (IN like) (S (NP (PRP it)) (VP (VBZ 's) (ADJP (JJR smaller))))))) (. .)))