Mad Men’s John Slattery Defends January Jones’ Icy On-Set Demeanor

 Gaye Gerard/Getty Images

Not everyone finds January Jones to be insufferable on the set of Mad Men.

On Tuesday, 11-year-old actor Jared Gilmore revealed he had to "be careful" around the 33-year-old actress, who played his cold and emotionally closed-off mother on the AMC hit. "She's not as approachable as the others. She's really serious about what she does," Gilmore said. "Everyone else is so nice."

(Gilmore left the show to star on ABC's new fantasy series Once Upon a Time, costarring Ginnifer Goodwin and Jennifer Morrison.)

According to another one of Jones' costars, actor John Slattery, the actress isn't as unfriendly as Gilmore described.

"Well, it's an intimidating character," Slattery, 49, told E! News. "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."

"She's a sweetheart," Slattery added. "We got lucky. We don't have anybody like that."

Currently pregnant with her first child (the father's identity has yet to be revealed), Slattery has "no doubts" Jones "will make a great mother" in real life.

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