Secretly Rich Son-in-law

As the son-in-law of Xavier family, Duane was shocked to hear that old Mrs. Xavier told him to take the fall for one of Xavier's heirs, Melvin. In their eyes, Duane was poor and nobody. 
Duane entered the Xavier family as the son-in-law three years ago. He was the subject of their disdain on a daily basis. But they did not know Duane hadn't married into the Xavier family for the money; he came for Lavinia, Xavier's granddaughter.
Now, Duane had to dial the number he had long been avoiding.
"Young lord, is it really you? Oh, thank goodness! I've been waiting for your call for so long." 
"I'm ready to claim the family fortune, but on one condition."