Given the task definition and input, reply with output. From the given sentence, extract the phrase (often noun or verb) that carries the given relationship. The generated phrase should be present in the sentence.

Given Relationship: 'be founder of', Sentence: 'Consider also Smith 's Castle at Cocumscussoc in Wickford , site of 17th century trading posts erected by Richard Smith , and Roger Williams , founder of Rhode Island .'
founder