Seven children, including a 7-month-old girl, died in a fast-moving fire Tuesday night in this farmhouse in central Pennsylvania, about 25 miles west of Harrisburg. The cause of the blaze is under investigation, but the grandfather of the children said he suspected a propane heater in the kitchen.

LOYSVILLE, Pa. — The father was making his rounds in his milk truck and the mother was in the barn, milking the cows, when their 3-year-old daughter smelled smoke and ran for help.

By the time the parents reached their farmhouse, it was too late: Seven of their eight children were killed in a furious blaze Tuesday night in Pennsylvania's dairy country.

The victims ranged in age from 7 months to 11 years.

As schoolmates, friends and firefighters mourned, neighbors in the heavily Amish and Mennonite area converged on the farm to help out with the chores Wednesday morning, a few arriving by horse and buggy. Even the grieving father, Theodore Clouse, kept busy, perhaps as a way of coping with shock.

“He seems he might be just as good as to keep a little busy,” the children's grandfather Noah Sauder told The Associated Press. “It's really hard, I'm sure.”

The cause of the blaze was under investigation, but the grandfather said he suspected a propane heater in the kitchen. The surviving child told her mother that one of the other children was playing with the smoke, the children's grandmother, Arlene Sauder, told the AP.

The fire gutted the farmhouse, leaving a blackened shell in the rolling hills of central Pennsylvania, about 25 miles west of Harrisburg. A car parked beside the house was burned to the bare metal, its windows shattered. In the morning, school bus drivers and other motorists slowed along the rural two-lane highway, awed by the damage.Clouse had left two of his children, ages 2 and 3, watching television around 10 p.m. Tuesday when he went to begin his milk rounds, police said. He was pumping milk at a dairy farm a mile or two away when he nodded off in his truck, authorities said.Soon after, the 3-year-old alerted her mother, who apparently tried to get into the house. Janelle Clouse ran to the homes of two neighbors before getting someone to call 911, then went with the child to the father's truck and banged on its windows, screaming that their home was on fire, state police said.Six girls and a boy died of smoke inhalation, authorities said: Christina, 11; Isabele, 9; Brady, 7; Hannah, 6; Heidi, 4; Maranda, 2; and Samantha, 7 months.Those who know the couple described them as hard-working people who raised cows, delivered milk and grew alfalfa and corn with the children's help. The youngsters' mother is six months pregnant, her mother said.

Noah Sauder grandfather