Complex sentence: Around 1700 Sir James Campbell, acquired Dunderave Castle and estate, he secondly married on 21st Nov.1732 Anne Callander, the daughter of John Callander, Laird of Craigforth, and widow of Colonel John Blackadder.
Split into simpler sentences: Around 1700 Sir James Campbell, acquired Dunderave Castle and estate. His second marriage on 21st Nov.1732 was to Anne Callander, the daughter of John Callander, Laird of Craigforth, and widow of Colonel John Blackadder.