WASHINGTON—Accounts from several White House staffers suggest Treasury Secretary Timothy F. Geithner and the president's live-in mother-in-law, Marian Robinson, have developed an unlikely bond, meeting nearly every night by the Green Room fireplace after Geithner has finished his daily economic briefing and Robinson has put her granddaughters Sasha and Malia to bed. "They're generations apart, but they've really hit it off," said aide Jennifer Bronner, who often sees the 71-year-old retiree from Chicago's South Side and the 47-year-old overseer of the nation's economy spend hours giggling and whispering together late into the night. "Last night I heard [Robinson] call Secretary Geithner 'Honeybee' when she offered him one of her famous chocolate-chip walnut cookies and a mug of hot cocoa. They share something that would warm the heart of even the most jaded old cynic." Despite his uphill battle against a worsening recession and failing global markets, Geithner's midnight chats with Robinson have reportedly taught him to take life one day at a time, not sweat the small stuff, and always save old nylons so they can be filled with potpourri and used to freshen sock drawers.