This is part of "Real Parents," an occasional series looking at the lives of ordinary families.

Mornings are little-kid time, when Melody Christensen takes Scott, 9 months, and Jessica, 3, to library storytimes and playgroups. Afternoons are for the big kids, when she helps Jason, 12, and Taylor, 10, with homework or activities.

The Issaquah mom, who had her first baby at age 29 and her last at 40, sometimes feels like she has two families, with two schedules (one coordinated with her ex-husband) and two sets of adult friends (moms' group for tiny tots/school network).

But it's also a second chance: Separation from her first husband, months of chemotherapy with her first bout of cancer, divorce and a second round of cancer treatment stole much of her time when her older kids were young. Her "miracle" babies — born after breast cancer treatment — let Melody and her husband, Rich, savor their sweet early years.

"I know how quickly they grow up," she said. "I'm just treasuring my time with these two. It's so precious."

As part of an occasional series profiling real parents, the Christensens opened their home to The Seattle Times for a day to share the challenges and rewards of parenting four children. In a step-family. After cancer. With a preteen coping with special issues.

"It's a pretty active household," Melody says.

Blending a family

The first room visitors see in the Christensens' house is the formal living room, now a large playroom with colorful murals, play kitchen, plastic slide and even a swing hanging from the middle of the ceiling. The household includes a dog, three cats and a fish.

It's a home centered around kids, where Melody happily chooses playing over housework. "I want to concentrate on what's really important."

It's a home where Rich first wondered, "Is there going to be any room for me?

They met working at their church, Eastridge Christian Assembly. He was a lifelong bachelor; she was a single mom who'd just found more cancer in her lymph nodes. Neither were looking for romance, but once it started, it wasn't casual dating, Rich said.

"Right from the get-go, it was a courtship," he said. Early on, she spelled out her health situation, including the fact she might never have more children. Rich accepted that: "Most people think they can have kids, but nobody really knows," he said. In six months, they were engaged, marrying in October 2000.

They assured Jason and Taylor, then 7 and 5, that they wouldn't move. "It was important to them to be in the same house, with the same school," she said.

"It's hard to come into a house where someone has already lived," Rich said. "But marriage is a give-and-take. I sucked it up. The kids had already been through so much."

Jason didn't take well to a new man in the house, and his challenging behavior — he was recently diagnosed with Tourette's syndrome and bipolar disorder — exasperated the difficulties of step-parenting. The children spend Thursday nights and every other weekend with their father, who is also active in their schools.

"We talked about how Rich wasn't coming in to be their dad; he was coming in to be my husband," Melody said. "To see us having a good relationship was the best thing for them. We let it grow from there."

The younger children, whom their older siblings adore, helped the new family bond but even so, "five years later, we're mixed up but not blended," Rich said, only half-joking.

"It's an ongoing thing," Melody agreed. "You don't just work out all the kinks in the first year and then everything's OK. "

The older kids each have a trick to make 9-month-old Scott laugh. The younger ones drop mom and go for their siblings when they're home from school. "People say that when kids are five years or less apart, they compete with the baby for mom," Melody said. "With a bigger gap, they compete with mom for the baby. And that was true. It was, 'Let me hold her.' "

With so much going on, Melody keeps a color-coded calendar to track each child's activities. She tries to schedule events with extended family — her kids' grandparents, three aunts and 13 cousins all live nearby — on weekends when the older kids are home.

Some summer days, she'd have eight kids — friends and cousins — on the swing set in the backyard, with the sprinkler going and Otter Pops handed out. They'd camp out in the play room or host a movie night with tickets, popcorn and lights out. "It's the little things the kids really enjoy and crave."

"Miracle" babies

If Melody hadn't divorced, she suspects she would have stopped with two. But she and Rich really wanted more.

Doctors recommended against it, warning that the hormones could encourage any malignancy left in her body. There's little research on the exact risks, especially for young women, Melody said. (The median age for breast cancer diagnosis is 61, according to the American Cancer Society.)

Jessica was conceived fairly easily, but after two miscarriages following her birth, the Christensens gave themselves one last month to get pregnant before Melody went back on the medication that would keep her in menopause.

"It was an emotional rollercoaster we were on," Rich said. "This was either going to happen or it wasn't. We couldn't carry on risking her not being in treatment."

Despite her two earlier babies, Jessica's difficult birth — 18 hours of labor — made her believe that the body does "forget" childbirth during a long gap between kids.

Scott's birth was easier, until they discovered the placenta detached; after birth, a team whisked Scott away to get him to breathe. Instead of videotaping what he'd expected to be a happy occasion, Rich started praying. "He didn't cry for 10 minutes," he said. "I was dying inside."

But the CPR worked, and a day later everyone went home. "Newborns are so resilient," Melody said. Still, they constantly checked to see he was breathing. "We still worry he could be disabled, but he's met all his milestones. He's so alert and interested in everything."

Trusting herself

As a parent and a woman, Melody learned to trust her instincts, even when they clashed with the experts.

Her doctor dismissed her concern over a breast lump, noting it was probably a fibroid since she was too young for cancer worries at 31. With a 9-month-old and 2 ½-year-old, she consulted a second doctor, who discovered it was malignant and started a course of chemotherapy and radiation.

When Jason struggled in preschool, his teacher kept directing Melody toward parenting classes, "like there was something wrong with me," she said. But she doesn't blame herself for her eldest son's behavior any more than she takes credit for Jessica's easygoing nature, which includes putting herself to bed when she's tired.

"I've had the whole variety of difficult versus easy babies," said Melody, who went through colic with Taylor and now erratic night sleeping with Scott. "It's nice to have the perspective of knowing each stage is for a very short time. As soon as you're sick of this period, they'll move on to the next."

Like a river

Jason was diagnosed with attention deficit-hyperactivity disorder at age 4, then doctors suspected he might have Asperger's syndrome, a form of autism. He was often out of control at home, with verbal and physical tics. "We'd say, 'Jason, be quiet,' " Melody said. "But he couldn't be quiet." His inability to sleep, manic behavior and rapid mood swings suggested bipolar disorder.

After seeing several doctors, psychologists and psychiatrists, they settled in with a team at Children's Hospital and Regional Medical Center's Bellevue clinic. "For a while, I felt like I was his treatment coordinator," she said. "At Children's, I feel like they've really got a handle on it."

Jason's teachers and friends know and accept his disability, and he's comfortable sharing his diagnosis, Melody said. She learned to advocate for him both in the educational and medical systems and hopes their experiences may help other struggling families.

He attends mainstream classes at a public middle school with an individualized education plan. When school started, Melody wrote a note to each of Jason's teachers, offering strategies for some of his behaviors, such as letting him chew gum to control vocal tics or run an errand for a break.

At home, they track Jason's sleeping and moods on a chart on the refrigerator, where they also check off his various medications. Counselors helped Melody find ways to help Jason stay on task and remain calm, including following a strict sleep and meal schedule and limiting screen time.

"He's really bright, really fun and really loving," Melody said. "He's got so much energy; once you get it going in the right direction, he's great."

She tries to view Jason as flowing water. "Instead of damming the river, you have to guide it, divert it to where you want it to go," she said.

She gives him a thumbs-up for a good job. "I really make an effort to give him positive reinforcement," she said. "Otherwise, all he hears is, 'Jason, stop that' all day long."

Wordy explanations don't work with him. "I learned to give simple instructions and repeat it in a firm tone of voice. If I used the same tone with my daughters, they'd be in tears.

"I get my skills all honed, then the next one doesn't need it," she laughed. "They need something else."

Stephanie Dunnewind: sdunnewind@seattletimes.com or 206-464-2091.