It has been awhile since I've done any genealogy research but I'm pretty sure I descend from the Matthew Madill you list here. Matthew's father was named Thomas and one of his sons is David. David was born in 1855 and died in 1932 in Shepparton, Victoria, Australia. The family migrated from Ireland to Australia in the 1840s and they were farmers. David was a farmer in Undera, Victoria. David married 3 times and to his third wife had my grandfather, who is almost 93 years old. He and his younger sister are the last remaining children of David (out of about 18). My grandfather took over the running of the farm and my Uncle still resides there.