BRANDON, Miss. (AP) _ Alex Wilkinson has a mobile home to move out of, three children to do Christmas shopping for _ and new orders to prepare for military action in Bosnia.

``I've been married 14 years and I haven't missed a Christmas with my family,'' the National Guard staff sergeant said as the news sunk in. ``It's just a bad time of the year. You never know what's going to happen when you go overseas.''

The Pentagon on Monday ordered 3,800 reservists from across the country _ including more than 1,000 members of the Army National Guard and Army Reserve _ to prepare for duty in the Bosnian peacekeeping operation.

In Mississippi, 250 members of the National Guard's 113th Military Police Company in Brandon and the 114th Military Police Company in nearby Clinton have been ordered to begin training.

The 113th, Wilkinson's unit, was last activated during Desert Storm, but only made it as far as Washington state. Now these weekend warriors and their families sit and wait for the call.

Robin Pack, married only five months to 25-year-old Marshall Pack, was philosophical about his possible deployment.

``He knows that's part of his job,'' she said. ``My job is to sit and wait and hope that things go well and he comes home.''

None of the country's reservists has been formally called up, but Defense Secretary William Perry said President Clinton would issue such an order later. Some of the reservists would be sent to Bosnia, but some would go elsewhere, including Germany.

The Washington Post reported today that a senior administration official has said Clinton is considering going to Sarajevo to visit U.S. troops later this month, after the final peace accord is signed in Paris Dec. 14.

The reservists will perform such functions as military police work and medical support, and they will be called to serve for 270 days, Perry said.

He said active-duty soldiers from 22 Army units in 10 states also have been notified.

Two U.S. soldiers based in Germany _ Sgt. Matthew Chipman, 30, of Beardstown, Ill., and Sgt. Todd Eichmann, 24, of Kansas City, Mo., both Army communications specialists _ were among the first 28 NATO soldiers who landed in the Balkans on Monday to begin setting up the peace mission.

Blanche and Don Chipman tried to accept the news about their son, who also served in Saudi Arabia during Desert Storm. They say this situation worries them more because the mission is not as well-defined.

``Here, we don't know. We just don't know what's going on,'' said the elder Chipman, a Korean war veteran.

In a letter to her son, Mrs. Chipman wrote: ``Be sure to keep your coat on outside because it's so cold over there.''

``The only thing that I worry about are the mines and the cold, cold weather,'' she said Monday in a telephone interview.

Eichmann's mother, Janice Webb, said her son called her from Germany on Saturday to tell her the news.

``He was mainly just trying to reassure me,'' Webb said Monday. ``He said, `I have my M-16 and my 9 mm ready.' I said, `That's not really what I want to hear.'''

Intellectually speaking, Webb called the peacekeeping mission overdue. But, she said, ``That's not the mother talking. The mother talking says no, because I don't want my son there. He probably wouldn't like to hear me say that.''

Back in Brandon, 20-year-old guardsman Jonathan Papizan said he doesn't agree with the peacekeeping mission.

``There's no point. We'll just get shot at and probably killed,'' he said. ``I think it's a big mistake.''

On the other hand, Papizan said serving in Bosnia ``will probably be fun,'' but he fears his mother's reaction.

``I know she'll probably call the unit and demand that I not go. She cried when I went to boot camp. I guess all mothers do.''