THE GREATEST GIFT OF ALL Lily Palmer is in for the Christmas of a lifetime When the nanny signs up to watch Dr. Cullen Dunlevy's four foster kids, she's got her hands full. The Thomas clan is the most mischievous group of youngsters she's ever had to wrangle, but Lily loves the job. After all, what girl wouldn't adore spending the holidays with a warmhearted new family--and their irresistibly handsome foster dad? Cullen doesn't mind Christmas, but...