Keane, who started drawing the one-panel cartoon featuring Billy, Jeffy, Dolly, P.J. and their parents in February 1960, died Tuesday at age 89 at his longtime home in Paradise Valley, near Phoenix. His comic strip is featured in nearly 1,500 newspapers across the country.
Jeff Keane, Keane's son who lives in Laguna Hills, Calif., said that his father died of congestive heart failure with one of his other sons by his side after his conditioned worsened during the last month. All of Keane's five children, nine grandchildren and great-granddaughter were able to visit him last week, Jeff Keane said.
"He said, `I love you' and that's what I said to him, which is a great way to go out," Jeff Keane said of the last conversation he had with his father. "The great thing is Dad loved the family so much, so the fact that we all saw him, I think that gave him great comfort and made his passing easy. Luckily he didn't suffer through a lot of things."
Jeff Keane has been drawing "Family Circus" in the last few years as his father enjoyed retirement.
Keane said in a 1995 interview with The Associated Press that the cartoon had staying power because of its consistency and simplicity.
"It's reassuring, I think, to the American public to see the same family," he said.
Although Keane kept the strip current with references to pop culture movies and songs, the context of his comic was timeless. The ghost-like "Ida Know" and "Not Me" who deferred blame for household accidents were staples of the strip. The family's pets were dogs Barfy and Sam, and the cat, Kittycat.
"We are, in the comics, the last frontier of good, wholesome family humor and entertainment," Keane said. "On radio and television, magazines and the movies, you can't tell what you're going to get. When you look at the comic page, you can usually depend on something acceptable by the entire family."
Jeff Keane shared the sentiment, saying "Family Circus" had flourished through the decades because readers continue to relate to its values of family moments.
"It was a different type of comic, and I think that was my dad's genius - creating something that people could really relate to and wasn't necessarily meant to get a laugh," he said. "It was more of a warm feeling or a lump in the throat."
Keane's friend Charles M. Schulz, the late creator of "Peanuts," once said the most important thing about "Family Circus" is that it is funny.
"I think we share a care for the same type of humor," Schulz told The Associated Press in 1995. "We're both family men with children and look with great fondness at our families."
Keane said the strip hit its stride with a cartoon he did in the mid-1960s.
"It showed Jeffy coming out of the living room late at night in pajamas and Mommy and Daddy watching television and Jeffy says, `I don't feel so good, I think I need a hug.' And suddenly I got a lot mail from people about this dear little fella needing a hug, and I realized that there was something more than just getting a belly laugh every day."
Even with his traditional motif, Keane appreciated younger cartoonists' efforts. He listed Gary Larson's "The Far Side" among his favorites, and he loved it when Bill Griffith had his offbeat "Zippy the Pinhead" character wake up from a bump on the head thinking he was Keane's Jeffy.
Keane responded by giving Zippy an appearance in "Family Circus."
Born in 1922, Keane taught himself to draw in high school in his native Philadelphia. Around this time, young Bill dropped the second "L" off his name "just to be different."
He worked as a messenger for the Philadelphia Bulletin before serving three years in the Army, where he drew for "Yank" and "Pacific Stars and Stripes." He met his wife, Thelma ("Thel"), while serving at a desk job in Australia.
He started a one-panel comic in 1953 called "Channel Chuckles" that lampooned the up-and-coming medium of television. (In one, a mom in front of a television, crying baby on her lap, tells her husband: "She slept through two gun fights and a barroom brawl - then the commercial woke her up.")
He moved to Arizona in 1958 and two years later started a comic about a family much like his own. Keane and his wife had a daughter, Gayle, and sons Glen, Jeff, Chris and Neal - one more son than in his cartoon family.
"I never thought about a philosophy for the strip - it developed gradually," Keane told the East Valley Tribune in 1998. "I was portraying the family through my eyes. Everything that's happened in the strip has happened to me.
"That's why I have all this white hair at 39 years old."
Thelma Keane died of Alzheimer's disease in 2008 and was the inspiration for the Mommy character in the comic strip.
When his wife died, Keane called her "the inspiration for all of my success. ...When the cartoon first appeared, she looked so much like Mommy that if she was in the supermarket pushing her cart around, people would come up to her and say, `Aren't you the mommy in `Family Circus?"'
She also served as his business and financial manager.
Arizona and Keane had a mutual influence on each other. Keane's work can be found all around - from children's centers to ice cream shops.Likewise, Arizona could also be found in Keane's work.
A 2004 comic saw the family on a scenic lookout over the Grand Canyon with the children asking "Why are the rocks painted different colors" and "What time does it close?"
Jeff Keane said those memories endure.
"He was just our dad. The great thing about him is he worked at home, we got to see him all the time, and we would all sit down and have dinner together. What you see in the `Family Circus' is what we were and what we still are, just different generations."