In late October 1961, well past midnight, my grandparents Lucille and Florian Yeaton were awakened by their farm dog Bonnie.

“Why is she growling?” Lucille asked.

“There might be a bear in the barnyard,” Florian replied. “Yesterday, Bonnie and I discovered bear tracks in the apple orchard.”

He lit a kerosene lamp. Their late 18th century cape farmhouse in Mercer was not wired for electricity. Awake now, too, my 9-year-old twin brother, Don, and I shuffled to the ell kitchen, where Bonnie whined to be let out.

“You boys go back to bed,” my grandmother ordered, opening the kitchen door. The border collie bolted into the darkness, followed by Florian. He carried a 12-gauge shotgun and a bright lantern. We glimpsed the pigpen’s silhouette beneath a Hunter’s Moon and heard squeals of frightened pigs and Bonnie’s angry barks.

A single shotgun blast echoed across my grandparent’s dairy farm. Ten agonizing minutes later, Florian and Bonnie returned to the kitchen.

“Bonnie chased a big bear from the pigpen,” he reported. “The pigpen door is stove up, but the hogs are okay.”

(Two days later, Ralph True, a neighbor, shot the 490-pound bruin after it killed a sheep in his pasture. The bear’s paws, he told my grandfather, were “the size of dinner plates.”)

The following morning during breakfast, my twin and I listened to stories of the 13-year-old dog’s heroics. When we were infants, Bonnie protected my 5-year-old brother Robert from a rabid fox by nipping his hind legs, as she did with disobedient sheep, herding him back to the barnyard.

Months later when Robert started a barn fire, Bonnie’s incessant barks sounded the alarm. Grandfather doused flames with pails of rainwater from the cistern; mother tossed wet blankets on the fire and moved livestock to a pasture; grandmother hand-cranked her wall phone to contact local Ma Bell switchboard operator Beatrice. Bea was well suited to convey pleas of help because she monitored residents’ whereabouts by eavesdropping on phone conversations.

“An acorn doesn’t fall from a town oak without Bea’s knowledge,” grandmother remarked.

The village blacksmith Clarence helped to extinguish the blaze with a Smith Indian backpack fire pump. Clarence, a barterer who dabbled as a gentleman farmer, coveted Bonnie.

“Would you trade that dog for a scythe and a rebuilt hay-rig?” he queried.

Startled by the preposterous offer, grandfather nearly choked on his plug of chewing tobacco. He thanked Clarence for his help, turned and walked into the milking parlor.

In the spring of 1948, Bonnie arrived on the Yeaton farm as a sickly litter runt.

Lucille placed the puppy on a horsehair blanket behind the Home Clarion wood cookstove, and fed her bottled goat’s milk. Bonnie’s health deteriorated. At wit’s end, grandmother added the moribund puppy to a sow’s litter of newborn piglets and hoped for the best.

“We’ll know by morning if the sow adopts Bonnie,” she sighed.

For a week the pup seemed not to take a breath suckling a hind teat alongside six nursing piglets. Bonnie’s weight quadrupled in the care of a 300-pound surrogate mother. Optimism, however, was dampened by unanswerable questions: Had she imprinted to the pigs? Was her social and physical development compromised? As Bonnie grew, she repaid my grandparents’ faith by becoming a tireless worker and a loyal family dog.

One hot summer day in 1958, she demonstrated her mettle as a trustworthy watchdog. During a hay harvest break, my 6-year-old twin waded into the Sandy River and was swept away by its strong current. Mother dove in but could not swim well enough to rescue him. Bonnie calculated the current would carry Don past a gravel bar 300 feet downriver, which is where she sprinted, jumped in the water and dragged him ashore with her jaws clenching his shirt.

The following morning Bonnie sensed what my family knew: Don was traumatized. She and grandfather lifted his spirits in the cow barn. Florian sat on a squat three-legged stool facing a Jersey cow’s udder. Bonnie and two barn cats took their customary milking hour seats near him. Florian squeezed a teat and sent streams of milk arcing through the air, splattering the faces of Bonnie and the cats. Watching them lick milk from whiskers and noses was therapeutic for my brother. He laughed and cried uncontrollably, and he embraced Bonnie. She had prevented his drowning the previous day; that morning she breathed life back into him.

In April 1962, cancer stole Bonnie’s life. When her vomiting, diarrhea, panting and pain seemed unending, a veterinarian arrived at the farmhouse one evening to administer euthanasia. The task completed, the vet refused payment. My poor and grateful grandparents sent him home with four Mason pint jars of raspberry jam, two quart jars of maple syrup, a dozen yeast rolls, a dozen farm fresh eggs and a 1-pound block of their hand-churned bright yellow butter.

Grandfather wrapped Bonnie in the blanket she’d slept on since puppyhood. Using a pickaxe and shovel, he buried her by moonlight in the apple orchard. It was her favorite place on the farm. He spent the night awake in a rocking chair, mostly giving thanks to a grand companion that had protected his family and livestock from a marauding bear, a rabid fox, a barn fire and the near drowning of a grandchild. The following morning, Grammy said he should also have thanked Bonnie for listening to his weekly complaints about weather and stagnant milk prices.

That day’s rain was fitting as my siblings and I visited the gravesite. During supper, my heartbroken 5-year-old sister Gale said little and ate nothing. As the table was cleared, she carried her plate behind the wood cookstove and dumped its contents into Bonnie’s bowl.

“Since Boo (my sister’s name for Bonnie) will be going to heaven,” Gale announced, “she’ll need a full tummy.”

Much to her delight, the bowl was empty in the morning.

Ron Joseph is a retired Maine wildlife biologist. Several of his stories have appeared in Down East magazine. He lives in Waterville.