The WA bdm records show a Horace F (might be a typo for E) Kerr marrying a Margaret C Simpson in the East Coolgardie District in 1906.
And there is a Broken Hill connection:
http://trove.nla.gov.au/ndp/del/article/33084386Twin sons born in 1908 (with a Broken Hill and Sandstone connection) - the boys might be Alexander and Horace E):
http://trove.nla.gov.au/ndp/del/article/33291720