Sarah Jessica Parker, Matthew Broderick and James Wilkie Broderick attend the opening night for 'Charlie And The Chocolate Factory' at Theatre Royal on June 25, 2013 in London. Credit: Fred Duval/FilmMagic

When Sarah Jessica Parker’s son, James Wilkie, was a little boy, the actress once received a terrifying call from his babysitter. “[She said] his mouth was swelling, he was coughing and his ears were red,” Parker tells Us Weekly. Later, James Wilkie’s breathing became labored and his throat began to close. “She rushed him to the pediatrician,” says the Sex and the City star, 51. That’s where James Wilkie was diagnosed with life-threatening allergies to peanuts and hazelnuts, also known as anaphylaxis. 

But Parker — who is the spokesperson for the Anaphylaxis: For Reel campaign — tells Us she doesn’t live in fear of James, now 13, landing in the hospital. “He knows how to inform those around him of his food allergies, so that everyone is aware and can help him avoid his allergic triggers,” says the Divorce star. 

The designer says James Wilkie takes after his dad, Matthew Broderick. “He is clever, loves sports, asks smart and interesting questions and is a great storyteller,” she raves.

Parker and her husband of 19 years are also parents of twins Marion and Tabitha, 6. She and Broderick, 54, are determined to keep their three kids grounded.

“We choose to live in a city where we are surrounded by all sorts of different people, from all walks of life,” says the longtime Greenwich village denizen. “So we walk, we take the bus, the subway and we talk about what we see and how difficult life can be for countless others and that they — my kids — are privileged in having everything they need. However, they don’t have everything they want.”

That means when Marion and Tabitha turn 7 on June 22, they won’t have an over-the-top birthday bash. “We will have a family affair that the girls are very much looking forward to,” Parker tells Us. “That is the only theme.” 

Can't get enough of Us? Sign up now for the Us Weekly newsletter packed with the latest celeb news, hot pics and more!