updated - July 31, 2015 Friday EDT
White Castle is celebrating National Grandparents Day on Sept. 9 by offering the first 100 grandparents and grandchildren a vintage-inspired White Castle "I Heart Grandparents" cap.
The offer will be available at each of its 400-plus stores around the country on Sunday, Sept. 9, the company said in a statement. Grandparents can download a coupon -- good on Sunday, Sept. 9, only -- for four Original Sliders for $1.
"We look for opportunities to create memorable moments for our Cravers, and celebrating National Grandparents Day is a natural fit for us," said Jamie Richardson, White Castle vice president, in a statement.
"It's a chance for Cravers who grew up with White Castle to introduce their family to the Original Slider for the first time or even the 100th time. It's special to see the love of our food being shared among families that span several generations," Richardson added.
In 1978, Jimmy Carter declared the first Sunday after Labor Day National Grandparents Day with the help of Marian McQuade. This is the first time White Castle will celebrate the occasion.
This year marks the 34th year for National Grandparents Day but it's the inaugural Grandparents Day celebration at White Castle.
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