Ally is happily married to Luke. But she and her sister Miranda couldn't be more different. While Ally has four children and a cosy home life, Miranda is child-free, married to a millionaire and lives in a show home that wouldn't be out of place in the pages of HOUSE & GARDEN. Ally gave up trying to compete years ago. But she is shocked when Miranda asks her if she'll help provide the one thing that is missing from her perfect life: a baby. Ally has every sympathy for Miranda's infertility problems, but can she really have a baby and hand it over to someone else? Especially if that someone else is Miranda.