DADDY BY DEFAULT When Chicago sophisticate Clair Fletcher hit rough-hewn Elk Creek, Wyoming, seeking custody of her orphaned nephew, she thought she'd landed on another planet. And when she confronted rancher Jace Brimley, the mountain of a man who'd given his all to become the toddler's guardian, the oxygen whooshed from her lungs. Combining tantalizing brawn with heart-stopping tenderness, Jace clearly adored tiny, hero-worshiping Willy, who mulishly resisted Clair's inept parental efforts. Still, didn't Willy belong with his blood relative? Yet how could Clair battle big-hearted Jace whe.