"I don't think someone [wanted the painting] for resale," says Bazin, of Cherry Hill. "I think they have it on the wall."
Measuring about 25 by 28 inches and tastefully framed, the Rockwell hung in the foyer of the Grants' house on Harrowgate Drive in the township's Fox Hollow section.
"My father just loved that painting," says Susan Murta of West Chester. "He was devastated. He always thought we'd get it back."
Says her brother John Grant, 53, of Egg Harbor Township: "It was a special thing. It was 'the family painting.' "
John Grant was 15 when family members returned from Ocean City on July 2, 1976, and discovered the burglary. The thief, or thieves, had gotten in through a basement window, activating an alarm; township police responded but found nothing amiss.
Besides the Rockwell, a Sony Trinitron color TV and "my silver coin collection" were taken, Grant says.
The coins were removed from a safe, suggesting the intruders may have known what they were looking for.
"It remains an open investigation," says Carrie Adamowski, spokeswoman for the FBI in Philadelphia.
Robert Grant had acquired the painting after he accidentally punctured its bottom corner ("near the signature," says Murta) with a pool cue while playing in a Haddonfield home in 1954.
He bought it from the owner for less than $100. After the theft, an insurance company reimbursed the Grants $15,000 for the loss.
Like many of Rockwell's works, Boy adorned the cover of the Saturday Evening Post. The artist, regarded by some as too sentimental to be serious, nonetheless remains popular. And in recent years he has gained a measure of fresh critical respect.
"He remains relevant," says Stephanie Plunkett, deputy director and chief curator of the Norman Rockwell Museum in Stockbridge, Mass., where Rockwell died in 1978.
The artist's enduring public appeal means his work appeals to thieves, too: A Rockwell valued at $1 million disappeared from a storage unit in Queens, N.Y., in October.
Art-theft investigations have evolved since the Grants' Rockwell went missing in the 1970s, notes Bazin, who has provided information about the painting to international databases and to the International Foundation for Art Research.
An item and an image of Boy recently were published in IFAR's journal, executive director Sharon Flescher says.
"Many works of art are recovered 20 or more years after the fact," she adds. "This was a long time ago, admittedly. But one doesn't give up hope."
Says Bazin: "I am very hopeful this painting will end up back with its rightful owner."
Anyone with information about the missing Rockwell can call the FBI's office in Cherry Hill at 856-795-9556 or Bob Bazin at 609-933-2042.