Sentence:  Even when the deceptive mask was torn away, and the broken-hearted parent, beholding the accursed fact, that his darling son, the fancied <WSD>stay</WSD> of his declining age, was enlisted against him in his brother's horrible revolt, cursed them both and died, not even then did one compunctuous visiting touch his callous heart. 
Meaning of the word marked with <WSD> tags:  A prop; a support.