SANTA ANA, Calif. — Paula Duhn spent plenty of nights on the Internet, a nursing infant asleep on her lap, researching possible manufacturers in India or securing samples from China or learning how to get a patent.

All she had to do was look down to see the driving motivation behind this work, this overtime on top of overtime.

"My kids were a part of it whether they realized or not," Duhn said.

Many moms think of a great idea. But for most, that's as far as it gets. Duhn is among those mothers who have actually nurtured and pushed and brought it to market. And in doing so, she has modeled determination, ingenuity and the value of believing in yourself to her children.

Duhn is self-employed doing mortgage loans. She often works more than 40 hours a week out of her cozy, cluttered home office, decorated with pictures of her kids and drawings they've done.

Behind her desk, in bins and on shelves in the garage of her Santa Ana, Calif., home, is her real passion. Her invention. Duhn, 38, created a product called the Stay-Put bib, which comes with a Gund animal clip that attaches to the baby's shirt, preventing the bib from flipping up over the baby's head or dragging in food. The patented invention sells from her Web site, www.byamom.com.

She does this so she can afford to work from home, and to someday move with her husband and her kids out of the house they share with her parents.

"The hard work I'm putting into it, my kids see it, they see the time I spent and see it evolve into something. It's going to make them want to work hard. It's going to help shape them as individuals, to know that it's OK for women to follow their dreams."

Frustration, then light bulb

Her invention was really born, like most good ideas, out of necessity. Duhn's second child, Brandon, was an infant when she started looking for products that simply didn't exist. She was annoyed by bibs flopping over her babies' faces at an age when they couldn't pull it down. She went to the store looking for a bib that would stay put.

She couldn't find it anywhere. She figured she wasn't the only mom who'd want something like this. So she decided to invent one. Not that she had any experience.

"There was nothing stopping me other than time and money, of which I had neither," Duhn said. "It was really hard. I look back and I think, how did I do it? When my mortgage business was slow, I'd do research, globally and locally."

Five years and two more kids later, Duhn has a patent and a product. But not peace of mind.

"There's a lot of self-doubt, a lot of 'Wow, I don't know if I can do this, what if I'm wasting my time,' " Duhn said. "It's scary. If this doesn't work, I just put myself in a way worse position financially. I can't take no for an answer. I'll just keep going and going and going."

Tamara Monosoff started mominventors.com two years ago because she wanted other women to have the same option as she has: to work from home on something she loves.

Monosoff, 39, came up with the idea for a device that prevents toilet paper from being pulled off the roll by inquisitive toddlers. She did all the research and development for the product, from finding a manufacturer to securing a patent to marketing what she called the TP Saver.

She had no manual, no roadmap. She does have a doctorate in education and once worked for the Clinton administration but says her degree didn't help with her invention. What did push her along was her desire to be a good mother to Sophia, now 3 ½, and Kiara, 16 months, while satisfying a different side of her.

"Thinking of going back to your job or a job that takes you offsite and away from your family doesn't feel right," Monosoff said. "But I also need to have intellectual stimulation. I don't enjoy being full time at home. I do love my children passionately, but I wanted to be able to combine the two. It is not easy. But it's doable."

Monosoff's husband, Brad Kofoed, quit his executive job to help Monosoff with her business. They license mom inventors through their Web site, doing all the legwork to get ideas into production and out on the market. They also run the Web site to help ease the way for other mom inventors, and started a mom-inventors-only eBay store.

She and her husband work from 8 a.m. to 4 p.m. in their home office in Walnut Creek. Then they walk out of their office, leaving cellphones behind. They are with their children from 4-8 p.m. Then they are back in the office until midnight.

"You can't imagine how many moms are online at that hour," Monosoff said. "It's the only way to do this."

Fluidity, not balance

There is no such thing as "me" time.

"The whole idea of balance, it doesn't make sense to me," Monosoff said. "There's always that wish to fit into that pair of jeans. You're kind of setting yourself up for failure if you're always trying to achieve balance. It's like a scale that goes up and down. Life isn't about balancing the scale evenly.

"It's got to be a fluid movement. I'm passionate for family and passionate for business."

Duhn is confident that working from home will pay off for her family. She's not sure if her product eventually will.

Still, the incentive is constant. Especially when she gets a little reminder that what she's doing is having a positive impact on her children. Brittany, 10, was asked at school to write about her role model. Duhn cried when she read it.

"My role model is my mom. She makes good choices, says positive comments and she works really hard. She takes care of all of us, and she tells me about the stuff I need to know. She tells me to think before I act. Her positive message is to respect others. I really look up to her."