I am hoping that Katherine is still researching and active on this or other boards.
I have a Robert Ireland Pryde b28Jun1903 (wife's genealogy)
Also have all other names (right sequence but one or two dates close but not exact) and confirm the other names you mention as children of William Ireland Pryde and Helen m.s. Robertson.
I have still to confirm my data re Robert (relative's recall) but have Robert "bob" Ireland Pryde listed as a cousin (and 12th child of Andrew Pryde, William's brother)
If you are still active and interested please post a reply