COLORADO (KUSA) -- A Colorado family is planning to file a civil rights lawsuit after a school banned their transgender 1st grader from using the girls' restroom. Six-year old Coy Mathis was born male, but wears girl's clothing.

The mother of six-year old Coy Mathis, Kathryn Mathis, said in a news conference that she was saddened by the school's decision.

"In the end, we just want what's best for Coy," explained Mathis.