Answer: blueboy

AnswerCrossword Clue
BLUEBOYGainsborough masterpiece.
BLUEBOYArt treasure of Huntington Gallery, San Marino, Calif.
BLUEBOYSubject of famous painting.
BLUEBOYGainsborough work
BLUEBOYThomas Gainsborough masterpiece, with "The"