Life is tough when you're four years old and your daddy is a soldier fighting in a far-away war. But Abigail finds a way to be brave when her grandmothers create a dinosaur costume using magical thread. With the dinosaur snapped to her green pajamas, she promptly names him Rumpus. Although Abigail's own ears don't hear as well as other children's, she quickly discovers that only she can hear the dinosaur's deep voice.
Together they begin a year-long exploration of her grandparents's Texas ranch, where their adventures include bottle feeding a baby calf, learning the proper way to call an elk, and finding a suitable tail for a tailless monkey. Singing "Jesus Loves Me" gives the two friends courage while meeting a room full of wild animals. Explaining to Rumpus that Dear Lord is always with us, even though He is invisible, helps Abigail be brave.
But will her friendship with Rumpus, and her belief in the Dear Lord be strong enough to comfort Abby the entire twelve months her daddy is away?