Pretty cool idea, better than wearing a watch I think.  Would offer some piece of mind, especially if you could track it like an i-Phone.  For example, if you went camping and were able to know exactly what direction to go to find your child.

In 2014, Thierry foundedIndependence Day Clothing, which offers shirts and pants that can help track down a child in the event he or she goes missing.

http://www.huffingtonpost.com/2015/02/18/autism-gps-device_n_6705368.html