Shinic's evolutions through growing up:

Evolution 1: Shinic looks similar to Sonic, though he is pretty thin and is missing his ears and torso details. His shoes also lack detail, his eyes are more black and he has an almost exposed ribcage

Evolution 2: Shinic is slightly taller, having longer limbs and an elongated mouth, exposing the gums more

Evolution 3: Shinic becomes a freakish giant, with the limbs elongating again and the mouth widening, now only crawling on all fours

Evolution 4: Looks similar to Evolution 3, though Shinic is way larger, with each of his hands being twice the size of Knuckles, and his mouth is way wider

Evolution 5, the last one: First seen at the end of Cry of the Forest and primarily throughout Chaos, Shinic's fifth form has a similar appearance and build to his previous two forms, though he is now as tall as mountains and skyscrapers. He also gains a second set of teeth. It also revealed that despite his immense size, he is still capable of moving at supersonic speeds, meaning that the destruction he could cause by running around the planet would be world-ending

One day, as you were walking you saw a sign reading "Free baby hedgog", this was weird...but you approached anyway, you then saw a baby Shin Sonic, or aka, Shinic, this was pretty weird...you picked him up before he screeched at you