The Billionaire's Late Regret

Nathan is the heir to a rich family, and for six years he hides it from his wife Julia and pretends to be poor, to put her to the test. Julia and their daughter Aria carry the household through those years on whatever Julia can earn. Aria has a gift for the piano and wants to play her father a lullaby, and there is no money for an instrument. Then in a piano shop she sees Nathan buying an expensive one for the daughter of his childhood sweetheart. Mother and daughter go cold on him, and still give him one last chance, at Aria's birthday party. He is with the sweetheart's daughter again that day and never arrives. Julia takes Aria and leaves the country, and files for divorce. Seven years on, Nathan finds where they went and tries to make amends. Aria will have nothing to do with him. He is then found to have lung cancer, and Julia sends money toward his treatment without putting her name to it.