A lot of people will end up in the doghouse over the holidays for being tied to their smartphones when they're supposed to be eating a family meal or opening presents under the tree. Some of the worst offenders of all will be the self-employed.

There's just no rest for the weary entrepreneur. There's no boss looking over your shoulder, but if you take a break, so does your whole business and livelihood.

That's how Megan Smith ended up on a 30-minute conference call on Christmas morning.

"Last year, Christmas Eve, I guess it was Christmas Day at that point," explains Smith, "a little after 3 a.m. was a flurry of text messages from one of our tech-startup clients."

Smith started her Philadelphia public relations firm back in 2007 and it's still small. She describes it as very hands on, to the point of agreeing to her client's request for a consult on his new ideas the next morning.

"It's like, darn it, I don't want to, because I'd really like to be eating pancakes right now. Mine are getting cold as I'm talking to you on the phone." she says. "But you want the client to feel like they're the No. 1 priority always."

The company is hers, so if it fails -- as young companies often do -- she will feel wholly responsible.

She thinks all the hustle is part of a startup mentality.

So does another of her clients, Keith Leaphart, who took over a print shop called Replica in Center City three years ago and revamped it. He says he'll start checking his Blackberry first thing Christmas morning. He'll text his employees on their day off to wish them a Merry Christmas, "but at the same time I'll be saying, 'hey, we got a job in. Hey, look for this. It's coming through.'"

Leaphart says his employees accept these holiday greetings cheerfully because they're happy the business is growing. But there's another group of people in this equation. Constant work can all be a little hard on families.

'Always one more thing ...'

"You just think there's always one more thing that you could do that could put you towards being successful," says Marc Kramer of his work habits.

At a trade show in Philadelphia to launch his newest startup, he says he's launched 20 companies since 1984. He teaches at Penn's Wharton School of Business and Temple University. Once he taught two classes at the exact same time with a creative use of guest lecturers. He has worked in rural Panama from his laptop while his family was on the beach.

"My girlfriend thinks I'm a workaholic," he says. "And I don't think I'm a workaholic."

"Absolutely, he works six, seven days a week," says his adult daughter, on the phone from New York. "I don't think he every really takes time off."

Ariel Kramer says he may have worked right up to a family meal but he always took a break to join in while she was growing up. She also thinks the boundaries between his work life and his home life have gotten clearer over time.

"I live in a different state now, so when I get home we try to make time for each other," she said.

Back at the business expo, Kramer says Ariel and the rest of his family play an important role. They set some limits on the time he'll stay at work, even though he's in his element at events such as the expo.

"I think you really need somebody who understands that but also slaps you. And says, 'Wait a minute, you have to have some reality here and have to dial down.'"

Hopefully "dial down" literally. Kramer and his daughter will spend the holidays together.