“It’s such a big eat-out occasion because mothers don’t have to worry either about cooking, cleaning, or, if she’s invited to her adult children’s home, imposing,” says Clark Wolf, a New York food and restaurant consultant.

Mr. Wolf recalls another motivation for taking Mom out on Mother’s day: “I remember it being the first time we had a polite excuse not to eat Mom’s postwar, freeze-dried cooking,” he says with a laugh. “And she didn’t need to feel insulted that we didn’t want her to cook.”

But on a more serious note, Wolf says the brunch tradition has become even more important o families since Sept. 11.
“One of the few social changes that has stuck since then is the trend toward more multigenerational eating within families,” he explains, adding: “This falls under the life’s-too-short category.”

“If restaurants succeed in making it a happy day for everyone, they have gained customers for life,” says Wolf. “For special occasions, we all go back to the places we love, where we can celebrate not only the familial but also the familiar.”

But on Mother’s Day. This ritual appears to be in full swing, and unlike on Valentine’s Day, a more-the-merrier approach often takes precedence. “No one feels slighted if you have three generations of moms at brunch,” says Wolf.