The Internal Revenue Service may have righted a wrong, but the 12-year-old Chesapeake, Va., boy whose $10.35 bank account had been seized because his parents missed a payment on an overdue tax bill will not easily forget the encounter. He even sent a letter to President Reagan about the incident. Now Gary D. Keffer has his money back, but says, "I'm afraid if they can do it once, they can do it twice. I thought that was a low blow and it's going to take me a while to recover from it."

The seventh grader's bank account was seized because his mother's Social Security number was on it. To prevent future embarrassing seizures, the IRS has a new procedure to identify the true owner of an account and will no longer seize any account with a balance under $100. Several people from around the country sent Keffer money to replace the $10.35 taken by the IRS. When asked if he would put it in a commercial bank for safekeeping, he said, "I think I'm going to put it in a piggy bank. I know it's safe with me."

On the Book Beat

Simon & Schuster is attempting to challenge the constitutionality of New York's "Son of Sam" law in a suit filed in Manhattan federal court. The suit is in connection with Nick Pileggi's bestselling book "Wiseguy," the story of Henry Hill, a self-confessed mobster. The book has sold 90,000 hard-cover copies and about 1 million in paperback.

The suit claims the New York State Crime Victims Board notified the publisher that "Wiseguy" fell under the "Son of Sam" law that bars criminals from profiting from any books written about their crimes. It is called "Son of Sam" after the serial killer who stood to profit from relating details of murders he committed in the 1970s. The Crime Victims Board has demanded all of the royalties already paid and any in the future. That amounts to a nice piece of money, since some $96,000 has already been paid on Hill's behalf to his literary agent ...

Another certainly profitable book has been proposed by a literary agent on behalf of Imelda Marcos, for an autobiography tentatively titled "My Hidden Wealth." But New York magazine says Marcos is not going to answer the question raised by the title. The eight-page proposal quotes Marcos as writing: "You can search the deepest and darkest vaults in Switzerland, you can comb the length and breadth of the United States and you can dig up all 7,100 islands of the Philippines, but you won't find it. Only Ferdinand and I know where the hidden wealth is deposited."

Out and About

Mikhail Baryshnikov, who injured his ankle in Atlanta last week and reinjured it Sunday during a performance in Jacksonville, Fla., has been ordered to stay off his feet for a week to 10 days. The American Ballet Theater artistic director has canceled part of his southern tour, including a benefit performance tomorrow for Tallahassee's Big Bend Hospice, which is now refunding tickets sold to 1,515 people ...

Milestones: England's ever popular and much loved Queen Mother Elizabeth celebrated her 87th birthday yesterday and appeared at the balcony of her central London home, Clarence House, to acknowledge cheers from the crowd below. Still active, the Queen Mum, as the mother of Queen Elizabeth II is affectionately known, has attended 65 public engagements this year, visited Canada in June and was in West Berlin for three days last month. At a recent visit to a tavern in the East End, she declined champagne and drank a pint of beer, which she declared to be excellent. No wonder they love her ... Ezra Taft Benson, who for eight years was President Eisenhower's secretary of agriculture, celebrated his 88th birthday Tuesday. Benson is now president of the Mormon Church ...

One would have thought there were other places to find out about boomerangs, but then the Smithsonian Institution has experts on nearly everything. The Chinese Golden Dragon Acrobats, now appearing in the Kennedy Center's Concert Hall, once had a boomerang act, but haven't had one for several years since losing their boomerang master. Tonight after their performance, Ben Ruhe, Smithsonian curator of boomerangs, will be backstage teaching the performers the art of the boomerang ...

"Most Americans are heterosexual and monogamous. Some of you may find that difficult to believe, especially if you enjoy watching daytime TV. According to the daytime soaps, the only reason someone gets out of bed in the morning is to jump in someone else's bed in the afternoon ... " So said Surgeon General C. Everett Koop, advising Americans not to panic about AIDS, at the International Platform Association's Washington convention at the Grand Hyatt Hotel ...