Pinocchio was a child when Charming was an adult in season one during flashback.
Remember, baby Emma didn’t exist with six-year-old Charming. Charming was twenty when Emma was born and Pinocchio was seven (and human).
Realistically Pinocchio can’t be seven when Charming is twenty AND when he was six.
Pinocchio is a wooden boy when Charming is age six and a real seven-year-old boy when Charming is age twenty. I suspect Pinocchio was wood for a long time. His adventure stretched out longer than we saw. And he wasn’t aging while wood. So he had an extra twenty or so years of wooden childhood before turning into a real boy and joining baby Emma in the wardrobe.
Crap, I hate noticing giant, glaring continuity errors after a good episode. I swear, the writers of Once Upon a time make me less insecure about my own poor math skills.