Think about this Wisconsin case:

A Wisconsin couple failed to seek medical attention for their 11-year-old daughter, who died from untreated diabetes.  They were convicted of second-degree reckless homicide and recently sentenced to 30 days in jail each year for the next 6 years, as well as 10 years’ probation.  The parents failed to seek treatment for their daughter and instead prayed for their daughter’s health, even when their daughter stopped being able to walk or talk.

As you know, diabetes generally is not a medical emergency.  However, when left untreated, it becomes an emergency. In the Wisconsin case, the parties were in agreement to not treat the child.  However, in the case of divorced parents, I would assume that both parties would not agree to not medically treat the child.  How do you deal with this??  Unfortunately, there is no easy formula and thankfully both parents are usually on the same page when it comes to the well-being of their child.  However, with some illnesses there are lots of different treatments such as diabetes, mental health, physical disabilities, learning disabilities, etc.   Therefore, if you have joint custody, regardless who is the residential parent, no one has superior rights regarding the choice of treatment.  If you and your spouse differ on how to treat an illness, and you believe your way is the best way, unless it is an emergency, you cannot make a unilateral decision.   I would suggest to contact an attorney immediately if you and your spouse are unable to agree on a resolution when faced with treatment options.