Cityfile encountered a stubborn mystery this week: Why did Huffington Post co-founder Ken Lerer help People magazine reporter Joey Bartolomeo buy a $1 million Upper East Side apartment? Bartolomeo and Lerer were mum, but we've found a (mundane!) answer.

Many people have criticized The Huffington Post for not paying its writers. But Ken Lerer, who co-founded the site with Arianna Huffington and remains the company's chairman, sure has one heck of a generous streak. Last week, we noticed that Joey Bartolomeo, a senior writer at People and frequent TV talking head, had purchased an apartment on the Upper East Side. What was strange was that Bartolomeo didn't buy the $1.025 million co-op on her own. Lerer's name appeared on the property documents as well. And it turns out that Joey isn't the first member of the Bartolomeo family to have benefited from Lerer's largesse. Bartolomeo's older sister, Stephanie Bartolomeo, picked up a $1.25 million co-op on the Upper West Side back in March. And once again, Lerer co-signed for the apartment.