Thanks for your reply. The children are
Annie 7 Feb 1878 Leyburn, QLD
Rebecca 31 May 1879 QLD
Eliza 16 Jul 1880 QLD
Rose Ellen 30 Oct 1882 Inverell, NSW
John Edward 1884 Inverell, NSW
David James 17 Jul 1886 Stannifer (near Inverell), NSW
Joseph Gladstone 1888 QLD
Timothy Joseph 18 Jul 1890 QLD
Catherine 30 Aug 1893 Crocodile Creek (near Rockhampton), QLD
Margaret was between 24 & 28 yo at Annies birth. On Annies birth cert she says she was 27yo.
The marriage occurred on 7 March 1877 (or possibly 1876 according to one birth cert which may have been a mistake as all the others say 1877).
Any ideas much appreciated.