Task: Question Answering
Input (English): passage: Ross Poldark is the protagonist of the series. In his autobiography, Graham states that Ross's character was, in part, based upon a fighter pilot he met on a train during World War II. In the first novel in the series, Ross Poldark, he learns upon his return home from the American War of Independence that his fiancée, Elizabeth, has given him up for dead and promised to marry his cousin, Francis. Life becomes bleak for Ross. A brooding and introspective character, he assumes his late father's estate, which includes a failing copper mine. Having lost Elizabeth to Francis, he marries Demelza, the girl he originally hired as his scullery maid, and they soon have a baby called Julia. Over the next 20 years, five more children follow: Jeremy; Clowance; Isabella-Rose, Henry and Bella.
 question: does ross and demelza stay together in the books?
Output (English): Yes