By Jill Smolowe
Updated December 10, 2012 12:00 PM

While growing up in Turner Station, a blue-collar community east of downtown Baltimore, Kevin Clash existed in what he would later describe as “kid heaven.” Not only did Clash and his three siblings outnumber their parents, but thanks to a day care center that his mom, Gladys, ran out of the family’s house, the two-bedroom brick home was a magnet for neighborhood kids, whether clients or not. A keen observer, Kevin digested several lessons by watching his mom-how to improvise, delight in kids’ points of view, remain positive amidst the mayhem-that would later inform his wizardry as a puppeteer, most notably as Sesame Street’s beloved Elmo. “My mother set a powerful example for me,” Clash wrote in his 2006 memoir My Life as a Furry Red Monster. “Like my mother, like Elmo, I strive to touch the heart of every child I come into contact with.”

Now, allegations have surfaced that Clash, 52, touched more than just the hearts of two underage boys. The first to level charges, Sheldon Stephens, 24, alleged that at age 16 he had sexual relations with Clash. To safeguard Elmo’s reputation, Clash promptly took a leave of absence from Sesame Street, but denied the charge, describing himself as “a gay man” whose relationship with Stephens was “between two consenting adults.” Stephens soon recanted. A week later, as reports circulated that Stephens had accepted $125,000 from Clash to retract the charge and now wanted to return the money and press charges, a second accuser came forward. In a $5 million lawsuit, Cecil Singleton, 24, a criminal psychology major at CUNY, alleges that when he was 15 Clash “persuaded, induced, coerced or enticed [him] to meet him for sexual encounters.” It was mostly “mutual groping and making out,” Singleton, who claimed he met Clash on a gay chat line, told PEOPLE. “My feeling is Kevin is a predator.”

Facing an expired statute of limitations on criminal charges, Singleton went the civil route “to stop Kevin Clash from harming any more people,” says his attorney Jeff Herman. On Nov. 20 Clash announced, “I am resigning from Sesame Workshop with a very heavy heart” in order to resolve “these personal matters privately.” Herman has told PEOPLE that Clash is facing a third accuser, who is also filing a federal lawsuit, claiming the puppeteer had relations with him when he was 16. A spokeswoman for Clash told PEOPLE the case has no merit.

Clash’s colleagues, meanwhile, are offering the beleaguered puppeteer-who is divorced and has a teenage daughter-their strong support. “Kevin is one of the most creative, wonderful, most prepared people I’ve ever had the pleasure to work with,” says castmate Martin Robinson. “I have serious questions about these allegations.” Fran Brill, who voices Zoe, says Clash has been “brilliant, funny, caring and completely consumed with maintaining the excellence of Sesame Street.”

Certainly, the charges grate against Clash’s reputation as the warm, loving guy who in 1984 took on the voice of Elmo, a B-list Sesame Street character that had stymied two puppeteers, and built the red moppet into a megastar. As Clash has accrued numerous Emmys, “he has been consistently generous with his time and talent, wanting to bring joy where he can,” says Cheryl Henson, daughter of Muppets creator Jim Henson, who cites Clash’s outreach to Hurricane Katrina victims, military families and children with illnesses. Now, while Sesame Street works to replace him, Clash is fighting to hold on to that reputation that has taken him-and Elmo-decades to build.