The children of baseball Hall of Famer Willie Stargell say they were blindsided by an auction of their dad’s treasures.

They said on social media that Stargell’s widow, Margaret Weller-Stargell, is auctioning the two-time World Series champion’s most valuable items.

“We are his grown children and were not honored, forewarned or offered the right of first refusal to make a fair offer on Dad’s belongings,” a Facebook post states without disputing her right to sell.

The sale is expected to raise about $500,000.

Bidding opened Wednesday.

The SCP auction includes Stargell's 1979 National Most Valuable Player Award.

It’s the same auction where a Peachtree City man plans to sell a rare Honus Wagner card that could fetch $1 million, The Atlanta Journal-Constitution previously reported.

Willie Stargell Jr. on Wednesday told Channel 2 Action News that he and his siblings tried to get Weller-Stargell to agree not to sell the items, but she refused.

"We were blindsided by it," Stargell's daughter, Dawn Moore Stargell, said.

They want to keep the memorabilia in the family, or at the very least, have it at the Hall of Fame and with the Pittsburgh Pirates and Atlanta Braves, she said.

In a statement to the Pittsburgh Post Gazette, Weller-Stargell said the items will be in the hands of those that will appreciate the significance of them to the game of baseball and the Pittsburgh Pirates.

"We want to make sure it's available to everyone," Stargell's daughter, Precious Stargell Cushman, said.

Weller-Stargell said a portion of the proceeds will go to the Willie Stargell Foundation, the Baseball Hall of Fame and the Pirates charities.

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