A Man to Call My Own By Johanna Lindsey

After the sudden death of their father, Marian and Amanda Laton must leave their New England home and travel to their aunt's Texas ranch. It is a harrowing journey, but plain-looking Marian welcomes the challenge of their adventure, while beautiful Amanda complains at every turn.  And when they need rescuing, cowboy Chad Kinkaid is the strong, sexy hero for the job.  Amanda's beauty catches Chad's eye, but it is Marian's daring spirit and hidden passion that spark his desire for her a sensual attraction that lands them in a romantic entanglement Marian is not prepare to handle.  Tied to him by the fate of her aunt's ranch, Marian must face a proud cowboy who's determined to convince her whether it means wooing her under the stars of the open range or following her back East that she's the only woman for him...