William Parker is shown to be the son of James Parker and Joane Drake, with a royal and Magna Carta ancestry. What evidence is there for this? This is not a recognized lineage. Should these parents be detached?
There was a Joane Drake, sister of William and Francis Drake, who married John Drake, haberdasher of London, who died in 1639, per NEHGR 48:308 (1892). This does not seem to be the same family as that of William Parker.
The Scituate Historical Society website gives no origin for William Parker; see http://scituatehistoricalsociety.org/early-scituate-families/