James Embry, a 28-year-old Web editor at a Binghamton, N.Y., health-care company, chats online with his mother in Big Bear, Calif., from the office, exchanging anywhere from one to 20 messages with her during a typical workday.

On computer and cellphone screens in workplaces across the country, many young employees keep up daylong conversations with their parents, sharing what the weather is like, what they ate for lunch or what the boss just said about their work.

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