Robert Alan Mowbray Stevenson
Robert Alan Mowbray Stevenson ( 1847–1900 ) was a Scottish art critic , a cousin of the writer Robert Louis Stevenson and the brother of Katharine de Mattos . 
<triplet> Robert Alan Mowbray Stevenson <subj> Katharine de Mattos <obj> sibling <triplet> Katharine de Mattos <subj> Robert Alan Mowbray Stevenson <obj> sibling