Mary Ann Warren (nee Mitchell) B 1837 Cornwall

I am looking for information on Mary Ann Warren (nee Mitchell) B 1837, Cornwall.  Arrrived in Australia 1849 (SA).  Her husband Richard Albert Warren B 1830, Cornwall was the proprietor of the Ovens and Murray Advertiser in Beechworth.

I am looking for any information regarding Mary's life as I believe she was an active member in her community.