Where does “Parkinson” come from?

I can't write this sentence because the chain provided (Peter/Petre/Petrus/Πέτρος/πέτρος) does not connect to the headword "Parkinson." Parkinson is a patronymic surname meaning "son of Parkin," where Parkin is a medieval diminutive of Peter. The chain you've provided traces Peter back to Greek, but doesn't show how Peter became Parkin or how that became Parkinson. To write an accurate etymology sentence for Parkinson, I would need a chain showing: English Parkinson → English Parkin → English Peter (or its variants) → and then the subsequent steps back through Middle English, Latin, and Greek. Could you provide the complete chain for Parkinson, or clarify if you meant to assign a different headword?