When Pa Peachey comes home in a happy-go-lucky mood--and singing!--the family is concerned. Pa has never not been grumpy after work! But when Ma and siblings Ava and Ollie learn that Pa has gotten a new job--which means moving to an appealing new house--they are all pretty quick to get on board. Even McTavish the dog is excited to make a canine pal in the new park nearby. Only the youngest sibling, Betty, remains out of sorts--nervous about changing schools, making friends, and leaving behind the house where she and McTavish grew up. But McTavish, with his special canine senses--and his vow, as a "rescue dog," to save the family whenever need arises--knows how to help Betty regain her confidence and feel at home again.