You’re The One That I Want by Krystal Shannan

The rule: Get married and have a baby. When Grandpa Stinson dies, he expects nothing more than to keep his grandsons together, running the family's multibillion-dollar business. But he's got just one unfaltering rule: they have to get married and have a baby first. Nicolas, the youngest, was the only one with a fiance, so that should have been cake. Just ask Alison to marry him. Until Alison cheats… relationship, OVER. Dafni Gallo has been running away from entitled rich bastards for most of her life, so the last thing she wants is to get together with another rich guy. Problem is, her online crush, who she thinks is just a normal, nice guy, turns out to be the prince of a rail fortune. Nic doesn’t have much time to break down Dafni’s walls, but he’s going to fight for her. Maybe, just maybe, Grandpa Stinson knew exactly what he was doing...