Katie O'Malley, Baltimore District court judge and wife of the mayor, says their 11-year-old daughter Grace is as much to blame as anyone. The oldest of their children put "a new baby" on her Christmas wish list last December.

"I told her definitely no," O'Malley says now with a grin. "She jinxed me. We found out we were pregnant right after we gave Will's crib away."

It's always "we" and never "I" when she talks about her pregnancy. Is it a reminder to her husband, whose work sometimes keeps him away from home late at night and on weekends?

"There are certainly moments when she wants to throw me and my current job out the window," Mayor Martin O'Malley admits.

Or is it recognition that she and her husband wouldn't be able to juggle two high-profile careers, three kids and a new baby without the help of a large, loving family?

They have some built-in helpers with daughters Grace and Tara, age 10. Katie O'Malley's sister Mary willingly baby-sits. The mayor's parents live in Rockville and are frequent visitors.

Barbara Curran, the children's maternal grandmother, picks them up after school or camp and takes them to her house in Homeland. She watches them until Judge O'Malley finishes presiding over a docket at the Fayette and Gay streets courthouse (around 4 p.m.).

Then Her Honor takes off her robes and becomes Mom again, often stopping at the grocery store after she visits with her mother or sister for a while. Afternoons aren't as hectic right now as they are during the school year, when the girls are involved in soccer, basketball or lacrosse after school.

The crew usually gets to their small four-bedroom home near Lake Montebello sometime around 6 p.m. It looks like any other middle-class house except that if you arrive unannounced, a policeman parked across the street will stop you before you get to the front door.

Off with her shoes

Even the other politician in the family, Attorney General of Maryland J. Joseph Curran Jr., helps out. This evening Katie O'Malley's father arrives at their home bearing gifts: a carryout dinner of salmon and salad.

His daughter meets him at the door in a long, flowing maternity dress, pearls and bare feet. She hasn't had time to change out of her work clothes yet, but the first thing she does when she gets home these days is kick off her shoes. This pregnancy has been particularly hard on her legs, she says; otherwise she's been relatively comfortable. (If you don't count sudden cravings for Ben & Jerry's ice cream.)

But if this follows the pattern of her other pregnancies, O'Malley, who is 39, can expect her blood pressure to soar and she'll start having severe headaches -- symptoms of pre-eclampsia, which if left untreated can lead to a serious condition involving convulsions and sometimes coma.

Her obstetrician may have to induce labor before the Oct. 18 due date, as was done with the other O'Malley babies. Now, though, she looks perfectly content and at ease. Although she thinks she's bigger with this child than the others, she carries the weight gracefully.

The O'Malley household is a little more peaceful than usual because 4-year-old William, soon to be the elder son, has fallen asleep on his parents' bed after a tough day at camp. Grace is in the basement with the computer and Tara is on the deck playing with Lady, a boisterous golden retriever. Three cats slip through the house, trying to avoid the visitors.

O'Malley curls up in a wing chair in the cozy (she would say too small) living room, decorated with traditional furniture, lace curtains, a relatively new oriental rug and portraits of the children painted by her mother.

With a wave of her hand she dismisses the idea that her present life must be stressful.

"I was working full time and going to law school at night full time when the girls were born," she says. "I was studying for the bar, we had no money -- I was a law clerk -- when we found out we were pregnant again and had Tara 13 months after Grace."

She pauses. "This is a piece of cake."

'Incredibly organized'

When the mayor is asked if he was surprised to learn he was having another baby, he says, "They've all been a surprise."

Actually no one seems very surprised. "It's the norm, not the exception to have another little O'Malley around," says Joe Curran.

"I think things will go along pretty much the way they always have," his wife, Barbara, says.

The kids aren't as unanimous in their delight as the adults. Grace was excited by the news; Tara wrinkles her nose and says, "It feels weird." Will warns his mother not to be mean to him or it might be bad for the baby.

"It's going to be wonderful for Will having a baby around," says his maternal grandmother. Well, that's one theory. Her son-in-law has another.

"It's going to knock the little guy off his pedestal."

No one who knows Katie O'Malley seems to think she'll have any trouble juggling her present family, one more baby, a career and the politics of being a First Lady.

Her friend Sue Hazlett, who worked with O'Malley when she was a Baltimore County prosecutor, gives an example of why the mayor's wife is able to handle what seems like a chaotic and difficult life to most people.

Her son Benjamin has already been invited to Will's birthday party in November. Will, who is a huge Harry Potter fan, and a group of friends will be going to the second movie in the series the day after it opens.

"Katie is incredibly flexible but at the same time incredibly organized," Hazlett says. "Just thinking about her life sometimes exhausts me. Adding one more child to the mix will be fine. I worry about her sometimes, but she can handle it."

The O'Malleys haven't picked a name for the new baby yet. Katie O'Malley would like it to be Max, after her brother, or James or Michael.

Her husband loves Irish names and is leaning toward Sean.

"I've told him if he buys me another house he can name the baby Sean," she says. If that doesn't work, "I'll let him see what it's like to have four kids and four bedrooms."

"I'd rather not move," Martin O'Malley concedes. "It would be nice to have a little more equity in the house before we do." (They bought it in '95, moving a whole six blocks from their previous home.)

Since a new house isn't in the cards anytime soon, Katie O'Malley and her mother, who has an artist's eye, have been shopping for furniture and redecorating the children's bedrooms.

"My nesting instincts have taken over," she says. "I enjoy going out on the hunt."

Tara and Grace have paired up together in the attic bedroom, freshly painted and furnished. William has moved into Tara's old room, and his room has become the nursery.

After looking everywhere, including online, O'Malley and her mother found a maple crib at Babies R Us to replace the one that was given away. They spent the whole weekend shopping for it with Grace, Tara and Will in tow.

Valuable advice

When the baby is born, O'Malley is planning to take three months off before going back to work.

"I've been saving up my vacation," she says. "It's nice for them to have a little meat on their bones before you farm them out." (In this case, it's more likely that help will come to the house.)

She describes herself as a very cautious parent. As an example she explains how she cuts up a hot dog "a million times" before she gives it to Will. "You hear these awful stories. Martin asks me why I don't just put it in the blender."

Certainly the death of her younger brother Will from Reye's syndrome at 16 months is part of the reason she worries about her kids -- although perhaps not more than any caring parent.

"It has affected all of us and it always will," says O'Malley, who was 7 at the time. "He was such a dear little boy. It makes me realize how strong my parents are."

When her husband was elected mayor three years ago, she was given good advice from Dr. Patricia Schmoke, the First Lady who preceded her. You have to realize there are a lot of demands, she told her. Don't feel guilty when you have to say no. For the first year, the current mayor's wife says, she had trouble doing just that -- until she read an entry in her daughter Grace's diary.

Because First Lady duties usually take place at night or on the weekend, she wasn't missing work so much as time with her children.

"I read in her diary, 'We always have a babysitter,' " she says now. "When I read that I said, 'That's absurd. First Lady duties have to be on the back burner.' I saved that little diary as a reality check."

Her husband seems fine with that. More than fine. He knows his work keeps him away from his family more than he'd like.

"My kids are lucky to have her as their mother," he says. "It gives me tremendous peace of mind."

As for the new baby, he takes some comfort in the fact that with a boy the household's balance of hormones will be shifting in his favor.

"But," the mayor adds, "they're still one up on us with the cats."