WJAC-TV reports that staff members at the Everett store say this is the second year in a row that the anonymous donor has made such a gift.
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Store veteran Barbara Kearns says she's never seen generosity and humility on this scale before.
The Walmart staff has been making calls to families with the news, letting them know their Christmas gifts on layaway are paid off.
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Nobody knows who the secret donor is, not even the Walmart staff. They just call him "Santa B."
In total, the staff says the donor paid a total of $40,000.