2009 BMW has GPS. Activate it.
Not all do."BMW Assist" is an option and it's a lot like OnStar in that it can be used to track a stolen vehicle.Unless actually kidnapping is involved (as defined by law) or the child is thought by police to be in danger I doubt that it could be activated (although I could be wrong).
BMW WILL NOT ALLOW TRACKING OF VEHICLE UNTIL I HAVE COURT ORDER, SHOULD BE NEXT HOUR