Both shows air on the Fox network in the US and Emily told Metro that she has "talked" with her sibling about a guest spot on her sitcom.
"Zooey played my cousin on an episode of Bones a couple of seasons ago and we've talked about me coming in to do New Girl," Emily confirmed.
"We shoot on the same lot, so if we weren't so busy it might be really easy to swing on by and play a part."
Emily added that she "watch[es] every episode" of New Girl, which stars Zooey as the kooky Jess.
"It's hard to get a few hours off, let alone a couple of days to do her show," she explained. "[But] I hope it happens because I love her show."
New Girl airs on Tuesdays on Fox in the US - season two will debut on E4 in the UK later this month.
> New Girl, The Following, Raising Hope renewed by Fox
Watch a clip from season two of New Girl below: