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By Scott Huver and Jessica Wedemeyer

A mother's work is never done -- not even when that mother is Sofia Vergara. The "Modern Family" star's son, Manolo, is 21-years-old now, but Sofia says she feels like just as much a full-time mom as ever.

"I am a working mom, and my son is still my son," she said while promoting her upcoming film "Escape From Planet Earth." "As a mom, you never stop worrying."

What changes, it seems, is not the incessant maternal worrying but rather the set of worries that go along with her son's new legal-drinking-age status.

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"Now my worries are: Don't get in a car with anyone who is driving drunk," she says. "Don't be stupid. When he is in New York on his own, don't walk down a back alley. Use your head. Don't go alone on the train at three in the morning. Stupid things like that."

Sofia's busy working schedule -- and her son's place in the adult world -- means the mother-son duo spend less time together these days. Surprisingly, the Golden Globe nominee has discovered that it's not the time spent apart but rather the time together that causes the most maternal stress.

"I realized that when he is at home with me now, when he comes from college to visit, I don't sleep that night because I know he is out," she explains. "When it's one o'clock, it's like, 'Why are you not back? You didn't drink, right? If so, I will go pick you up!' And I can't sleep. But when he is gone, who knows what he is doing! He could be running crazy, naked or who knows what -- but I can sleep!"

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In 21 years, the hot mama still hasn't figured out how to put to rest her fears for her son, but she has learned some other important lessons about raising a child as a single working woman in Hollywood.

"I always say it's about learning how to delegate," she says. "You have to learn to trust people and to have people help you if you want to do both things [work and parenting] right. [If not,] you will end up not doing a good job of being a good mother. So it's good to be organized."

"I think everyone can do it," she adds.

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