It had been the vacation of a lifetime, three weeks in Hawaii from mid-December to early January. But after a 10-hour flight, Ron and Laurie DeFore, their daughter and son and her parents were tired and eager to be home.

At 6 a.m. Jan. 3, as they approached the driveway of their three-story home in Annandale, Va., they realized that something was wrong: The garage door was open."My first thought was a burglar," said Ron DeFore. His second was disbelief: The ceiling in the ground-floor garage was so water-soaked it was falling down in hunks. He opened the door to the room he calls "the shrine to my father," and cried, "Oh no! No! No!"

"When I heard his voice I froze in the driveway," said Laurie DeFore. "I didn't want to look. I knew it was bad."

All around DeFore, water was pouring from the ceiling and walls onto the photos and posters documenting the career of his late father, Don DeFore, a TV sitcom fixture from the early '50s to the mid '60s. As the good-natured neighbor to the Nelsons in "The Adventures of Ozzie & Harriet" and as titular head of the household actually run by the housekeeper, "Hazel," Don DeFore was an amiable TV visitor to millions of American homes for more than a decade.

As he surveyed the ruins of "the shrine," Ron DeFore wondered how much could be saved of the paper legacy of his father's life in show business.

"Water was dripping all throughout the house," he said, "gushing in some areas." The culprit: a broken hose to the washing machine. Water had short-circuited the garage-door opener.

INDESCRIBABLE: "There're no words that can describe the feeling," said DeFore. "You're not ready for this at all. It's like getting smacked in the head with a baseball bat. For the first few moments, you have no idea what the extent was."

The soggy memorabilia was packed up and shipped to the Chicago Restoration Center. The firm sent back a damage estimate of $26,000 and a 30-page itemized appraisal. DeFore selected what he wanted restored - his insurance company would pay for it. But some items were so damaged he chose to accept compensation, he said.

On May 27, DeFore's mother, Marion, was in town for a visit. DeFore, 47, a principal with Stratcomm, a Washington public-relations firm, sat with his mother on the patio and went through pictures.

"One of the most precious things that the Chicago company is still restoring is a 1953 or '54 L.A. Times Living section spread on our house in Brentwood," he said, adding that the house, with tennis courts, a pool and a guest house, was recently on the market for $4.9 million.

THORNY AND MR. B: To America, Don DeFore was Thorny and Mr. B.

From 1952 to 1958, he played "Thorny" Thornberry, the genial neighbor in "The Adventures of Ozzie & Harriet." From 1961 to 1965, he was George Baxter, a successful corporate lawyer whose household was virtually run by his housekeeper, Shirley Booth, as the title character, "Hazel." She called him Mr. B.

The DeFore memorabilia collection also reflects Don DeFore's career before television made him a household face.

DeFore did stage plays, three on Broadway, and more than 25 films in the late 1930s, '40s and '50s, most for MGM and Warner Bros. "My Friend Irma," in 1949, introduced the comedy team of Dean Martin and Jerry Lewis. In 1952, the three also did "Jumping Jacks."

"Martin and Lewis went on to become bigger stars than my dad, but at least at that time, he was a bigger star than they were," said his son.

"He played one of the very first next-door neighbor roles," Ron DeFore added. "This was a whole new phenomenon where these people were coming into your living room and they actually became part of your family."

Don DeFore was, said his son, very much like the friendly Thorny Thornberry.

In 1954-55 and 1955-56, DeFore was voted president of the Academy of Television Arts and Sciences and arranged the first national telecast of the Emmy Awards.

DeFore was honored on Ralph Edwards' popular television program, "This Is Your Life." The show surprised its subjects, hustled them to the studio and presented their life stories.

Secrecy was paramount. Marion knew, of course, and Ozzie and Harriet Nelson were in on it, too. The day of the show, the Nelsons were seated on stools at a little hot dog-and-Coke stand on Vine Street, supposedly rehearsing for their series. DeFore was behind the snack-stand counter playing a sales clerk.

At the studio nearby, the audience watched while the camera panned to Harriet, then to Ozzie, and finally to DeFore, who was shocked when he heard, "Don DeFore, this is your life!"

MR. AND MRS. DEFORE: Don DeFore was the fourth of eight children from Cedar Rapids, Iowa.

He had done community theater in Cedar Rapids, then studied at California's Pasadena Playhouse before appearing in Broadway plays, including "The Male Animal." He was 27 and part of that show's road tour when he met Marion Holmes, 22, a vocalist with the Art Kassell orchestra at the Hotel Bismarck's Walnut Room in Chicago.

"I thought, `What a phony name,' " she said. "I didn't like him at first. And he was the tallest man I ever dated - he was 6-2, I was 5-2."

They went with the cast of his play to see Danny Thomas' 2 a.m. show at a nightclub. Two years later, Valentine's Day 1942, they were married in Los Angeles, with Judy Garland as matron of honor.

After a singing career that had begun when she was 16 and included several recordings for Bluebird records, Marion DeFore was happy to stay home and raise their three daughters and two sons.

DON AND RON: One of his dad's pals was Ronald Reagan, like him, a Midwesterner. They starred in a 1952 film, "She's Working Her Way Through College." Reagan was president of the Screen Actors Guild; DeFore was a member of the board of directors.

"He and Ron Reagan thought a lot alike," said Marion DeFore. "When Ron was running for governor, Don would fly with him and stop in these small towns and introduce him. He campaigned for Reagan for a long time."

DeFore, active in California Republican politics since 1960, organized and promoted Reagan's first political event, at the Santa Monica Civic Auditorium.

Later, when Ron DeFore came to Washington as a Reagan appointee, first at the Peace Corps, then at the Department of Transportation, his father asked Reagan to sign one of those posters for him. The poster, of course, is part of the collection.

On Don and Marion DeFore's 50th wedding anniversary, in 1992, their five children and the grandchildren (there are 13 now) flew to Santa Monica to celebrate, returning for his 80th birthday in August 1993. Four months later, in late December, he died.