aub_walker on Family Tree Circles

HI My name is Aubrey Desmaond Walker and I am trying to find my ancestry on the Walker side, best I can do so far is GGGrandfather John Henry Walker (watchmaker) married Mary Lee (she was possibly married before to someone called Broad) as both names appear on some of her childrens Birth Certificates. John Henry born approx 1845 (York or Lincolnshire) england Died Rutherglaen Vic Aust 19th - 5 - 1899 aged 56 from throat cancer. Mary (lee) Born poss Cornwall about 1843 died 1943 at Heathcote Vic a couple of months before her 100th birthday, buried not known but most likely Heathcote Vic.
I believe they had 12-13 boys & 1 girl, I can only track down 12 boys & 1 Girl.