(WASHINGTON) KRON — 138 years of Easter egg hunting will continue Monday on the South Lawn of The White House. This year’s theme is “Let’s Celebrate!” and more than 35,000 people will be joining the First Family for games, stories, and, of course, the traditional egg roll.

The White House Easter Egg Roll has been an American tradition since 1878. The event was started by President Hayes and his wife Lucy.

It’s one of the oldest annual events in White House history.

This year’s White House Easter Egg Roll features five souvenir eggs, designed by graphic designer and blogger Joy Cho. The collection features four colored eggs with stamped signatures of the President and First Lady on the back, and one gold “Bo and Sunny” egg, with stamped “signatures” and “paw prints” of Bo and Sunny on the back.

The National Park Foundation (NPF), the official charity of America’s national parks, produces and sells the commemorative White House Easter eggs. Each child 13 years and younger who attends the White House Easter Egg Roll on the South Lawn will also receive a souvenir egg.

The eggs first became part of the tradition in 1981, when President and Mrs. Ronald Reagan hosted a hunt for wooden eggs that bore the signatures of actors, actresses, famous politicians, and athletes.