The Convenient Cowboy (Harlequin American Romance Series #1560)

WHAT A COWGIRL'S GOTTA DO… 

A wedding of convenience isn't exactly cowgirl Olympia James's dream—she wants the rodeo, not a husband. But marrying Arizona lawyer Spencer MacCormack will make a lot of other dreams come true. Spence needs a stable home to win custody of his little boy, and with Spence's help, Olympia can finally pay for her sister's tuition and hit the barrel racing circuit. 

But while the marriage is supposed to be just on paper, their chemistry is volatile…and the night they spent together weeks ago leads to a surprise: Olympia is pregnant. Soon the ranch is home to a baby, Spence's sweet cowboy son and feelings Olympia and Spence can't deny. This fake relationship is quickly getting all too real. Maybe it's more than just business…