Sorry - was replying to wivenhoe. As far as I can see it's only the parents who are buried at Dimboola.
1883 was a sad year for the family as I see Walter WINGATE, Margaret's father died 17 April, 1883. His will is on PROV and he left his watch to his grandson nephew Walter, 'as an heirloom to be kept sacred in memory of his grandfather.'
Edit to add - my mistake - see below
PROV shows that James ANDERSON died intestate but the record of where/how his estate was administered is not digitised. It can, apparently, be ordered and I wonder if this document might have information re the sons.
Judith