Hi Elizabeth and Ruskie,
At least that solves the question of who Matthew was! When I get to see the LDS film hopefully it will confirm the boys second names (is there or isn't there a P in William Thom(p)son McGavin?) as well as give their dates of birth. Did you see the comment on the Scottish thread, that for some reason on certain films only the girls were transcribed onto the IGI?
It's been drizzling here most of the day

, so I've been able to spend a couple of hours going through all the information I've been given without feeling guilty for not gardening or painting

.
Ruskie, to answer a couple of your questions, I think I put 2 and 2 together about Francis Marsh marrying a Mary Anna because on the Electoral Rolls on Ancestry for 1925, 1930 and 1936 Francis and Mary Anna Marsh are both living at the same address (and in 1925 and 1930 they are the only two Marsh's on the page).
I'm not too bothered about the Will's for James Harvey, Margaret and Matthew McGavin - I think they may be the children of Matthew McGavin - but of course if you ever found yourself with nothing to do

.
I got excited before when I discovered the NSW BMD site - there's a Janet Thomson with parents John and Janet who died in Sydney in 1893. I couldn't immediately spot any others in the family but it might be somewhere to start, and could tie in with Robert being in Sydney when he died ?? (or am I making 5 again!!).