Job Title: Comic-strip cartoonist Employers: News feature syndicates Openings: Develop an idea and get signed by a syndicate Salary Cap: Low seven figures Number of Jobs: About 250 in the U.S. and Canada

After three decades of chronicling the joys and sorrows of the fictional Patterson family in her popular strip For Better or Worse, cartoonist Lynn Johnston planned to close it out with a happily-ever-after ending this year. The daughter in the family, Elizabeth, who readers had watched grow up from a baby into a young adult, would marry Anthony, her high school sweetheart, and that was going to be that.

But in 2007, Johnston's husband shocked her with news he was leaving for another woman. So, like a lot of other baby boomers, the 61-year-old Johnston, a Pulitzer Prize nominee and the first woman to win the National Cartoonists Society's Reuben Award—the cartoon world's Oscar—picked up her ink pen and went back to work.

In the past, experiences like this would have made their way into the strip much the same way her experiences getting a dog or sending her kids off to college did—For Better or Worse was and is unique among comic strips because its characters actually aged over time—but Johnston instead decided to go back to the beginning and rework some of her earlier strips and story lines.

Now in any given week, the daily strip includes several new strips sandwiched in between the old stuff, as well as old scenes Johnston has reworked to eliminate dated references. "I recently showed John typing something but now you don't see what he's typing on," Johnston says.

Johnston had been working as an animator and medical illustrator when she drew some cartoons about being pregnant for her doctor's office and subsequently had them published in two books. Universal Press Syndicate saw them and asked if Johnston was interested in doing a daily comic, an offer that led her to dream up the semi-autobiographical strip about the middle-class Pattersons and their extended circle of family and friends. The strip took off, and has since become one of only a handful of strips to ever appear in more than 2,000 newspapers. Since the reruns began, only about 60 papers have dropped it. Johnston credits the appeal to the universal nature of the material and the amount of research she puts into it to make it as realistic as possible.

Johnston is closed-mouthed about her earnings—she'll only say that "I do well, and for a cartoonist, that's a miracle"—but she does receive some additional income from selling For Better or Worse-related merchandise through her website. Compared with a strip like Peanuts or Garfield, however, this ancillary income is minor, and Johnston admits that she hasn't been aggressive about going after it. "But at this point in time, I don't care anymore," Johnston says.

For now, she's enjoying getting back to the simpler roots of the strip's story. In its later years, the strip got complicated and serious, with a cast of 90 and multiple story lines. Taking it back to the start means drawing a young family with little kids again, a refreshing change for Johnston.

"People who've already read it are comfortable having it back in any form, and there's a whole new society of young families who are enjoying" it now, says Johnston.