What to do...

[ref2coach]

Below is the clip from our State's official website.
An official is prohibited from working in an athletic contest in which a member of his/her immediate family
- son, daughter, brother, sister, mother, father, husband, or wife - is playing or is serving as a coach for
either team. If an official is a teacher, the official is prohibited from working in an athletic contest if one of
the teams represents the school in which the official is employed as a teacher unless otherwise approved by
the Executive Director. All varsity assignments must be assigned by a recognized and approved TSSAA
Local Association.

In TN you would not be prohibited from working a sport at a school just because you child attends said school.