Moss felt the need to speak up for Jones, who plays Betty Draper in the drama series, after 11-year-old actor Jared Gilmore - Betty's son in the TV show - made claims last year that she was not as friendly as the rest of the cast.
Last August, shortly after Gilmore left his Mad Men role for a recurring part on ABC series Once Upon a Time, he said that Jones was "not as approachable" as other stars from the show and warned the actor taking over from him that he should "be careful" around her.
According to The Telegraph, Moss has now said of Jones: "January's really fun, a cool girl and a great mum. She's got her head in the right place. Everybody loves her."
After Gilmore's claims, Mad Men star John Slattery also came to the defence of Jones. He admitted that Betty Draper is "an intimidating character", especially "if you were a 7-year-old boy [or] her son", but insisted that the actress is nothing like her.
"She's a sweetheart," he said. "We got lucky. We don't have anybody like that. I have no doubts she'll make a great mother."
> 'Mad Men' January Jones: 'I hope Betty is more well-received'
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