Veterinarian and single mom Emily Hawkins' world is turned upside down when her precious little girl is diagnosed with a terminal illness. Only a bone marrow transplant can save 3-year-old Matilda Louise. Emily isn't a match, but she's determined to find someone who is, and that means tracking down Tilda's biological father and his filthy rich family, a family she believes would've preferred her little girl had never been born.

When she arrives in Big Falls, Oklahoma, nothing is the way she expected. Joey McIntyre, the billionaire's son who'd been her sweet teenage summer fling, is as handsome and smooth as ever, but he seems to fall hard for Tilda-Lou at first sight, and he's furious that Emily has kept his child from him—which makes no sense at all. Soon Emily begins to suspect that the version of history she's believed all these years, might not be the real one. And if that's true, she's done a terrible, unforgivable thing.

But none of that matters as Tilda's dire symptoms set in. The doctor advises Emily and Joe to give their girl the best Christmas ever. Fortunately, Christmas is what the Brand-McIntyre clan does best.

Emily and Joey put their feelings aside, coming together in a desperate search for a way to save their little girl against all odds.

But the truth is that little Matilda Louise is the one who's saving them.