"Well, it's an intimidating character," John, who plays Roger Sterling, told E! on Tuesday. "I mean, that's the character. Betty Draper is an intimidating woman I suppose, if you were a 7-year-old boy [or] her son."
Slattery, who has had only a few scenes with Jones over the years, said the actress is a doll on set.
"No, she's a sweetheart," the actor continued. "We got lucky. We don't have anybody like that."
On Monday, TV Guide started the latest run of headlines regarding Jones when the mag quoted Gilmore -- who is leaving "Mad Men" behind for ABC's "Once Upon A Time" - telling the next actor to play Bobby Draper, to look out for Jones.
"Be careful around January [Jones]. She's not as approachable as the others," Jared told the mag. "She's really serious about what she does. Everyone else is so nice."
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