With three young daughters it's really no surprise Jess has a no-nudity clause written into her contract, but her decision to stay fully clothes has nothing to do with motherhood. Nope, it's all about her granny and granddad.
The 33-year-old opened up to US Glamour magazine to chat relationships, feminism and the one and only thing that prevents her from getting her kit off in public.
"It would be weird at Christmas. And, I mean, really, if you look at the movies I have done, getting naked would never 'elevate' the picture."
Understood - no-one wants to talk tit over turkey.
But boobs weren't the only things Jess wanted to chat about. The actress also spilled the beans on how she discovered feminism.
"Where I was from, you had to answer to a man if he was the breadwinner. My mom told me that didn't need to be the case for me - I didn't need to rely on a man," she said.
Perhaps that explains why she only ever had two boyfriends? "Relationships can be tough, and I was engaged before. I've only had two boyfriends. In the first one, with Michael [Weatherly, star of NCIS], I didn't have a voice yet, and he was so much older.
"But now [with Cash] there are no more surprises. At around two and a half years, you're kind of like, 'Are we in it? Are we doing this?' And the easiest part? That would be snuggling every night."
Read the full interview in Glamour magazine on newsstands 13 May.
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