The parents of a 6-year-old Massachusetts girl with peanut allergies have sued a restaurant because she became extremely ill after eating a grilled cheese sandwich with peanut butter on it.

The lawsuit filed in Middlesex Superior Court against Panera and a group of New England Panera franchises alleges negligence.

Natick resident John Russo tells The Boston Globe his daughter was hospitalized after eating the sandwich ordered online Jan. 28. He says his wife mentioned the peanut allergy twice on the order.

He says he was told by a store manager that the mistake was due to a "language" issue and that the person who made the sandwich may have seen the word "peanut" and thought it was an instruction to add it.

A Panera spokesman declined to comment.

Sign up for the NJ1015.com Newsletter

Get the best of NJ1015.com delivered to your inbox every day.

Sign up for the NJ1015.com Newsletter

Get the best of NJ1015.com delivered to your inbox every day.

(Copyright 2016 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed)