(a) No person, by any means and with purpose to withhold a minor from the legal custody of his parent, guardian or custodian, shall remove the minor from the place where he is found.
(b) It is an affirmative defense to a charge under this section that the actor reasonably believed that his conduct was necessary to preserve the minor's health or welfare.
(c) Whoever violates this section is guilty of child stealing. If the offender is a natural or adoptive parent, or a stepparent of the minor, but not entitled to legal custody of the minor when the offense is committed, child stealing is a misdemeanor of the first degree unless:
(1) The offender removes the child from this State, or the offender previously has been convicted of child stealing or of kidnapping or abduction involving a minor.
(2) Physical harm is done to the minor.