She and her parents have since reconciled, but now, "I have strict boundaries in my head," she said. "I'm not going to write anything about my family that I wouldn't say to them in real life, in front of other people." Also, "a lot goes on in our marriage that I will never write about," including her and her husband's sex life, she added.

The time demands of sustaining what has become a brand name are incessant. Experts say keeping a blog fresh and topical is essential. But after posting most days for seven years, Armstrong has periods of writer's block so intense that they're "physically painful," she said. She carries a notebook almost everywhere, recording thoughts and ideas. To take a vacation, she has to pile up extra material. "Many nights I've gone to sleep crying because I want my life back," she said.

"The pressure on her to come up with something unique to say all the time would be enormous," said Susan Carraretto, co-founder of 5minutesformom.com, another popular site. Blackshaw added, "It's kind of like 'Mom meets "The Truman Show"' ... Everybody is watching" constantly.

Armstrong and her husband face marital strain from working so closely. "He and I have had our marital problems for sure, and we go to therapy all the time. We're together 24/7. I'm not sure every couple could do that, but he and I are best friends."

Neither expected to make a living this way. Heather Armstrong intended to quit blogging after her daughter was born in 2004 and be a stay-at-home mom for a while. But as she fell into a severe postpartum depression, she found blogging a valuable outlet and an antidote to the isolation she felt.

"Immediately I realized that writing things down and sharing it with people was getting me through the day," she said. A warm response from "this community of mothers" reading her posts "lifted me up and gave me the courage" to check into a hospital for four days and get treatment, she said. It was at the urging of her husband, a former Web creative director, that she made the transition from blogger to breadwinner in 2005.

These days, her posts are more sanguine, on topics ranging from tiffs with her mother over global warming to a freak fish found in a Utah pond. And her old plan — of going back to work as a Web designer — is history.

Hassles notwithstanding, she said, "Now I think, 'Wow, I'm so glad I stuck with this.'"