Me. Rev. Stat. tit. 28-B, § 507

A minor may not enter the licensed premises of a cannabis store unless accompanied by the minor's parent, legal guardian or custodian, as defined in Title 22, section 4002, subsection 5. An individual identification card holder who is the parent, legal guardian or custodian of a minor may bring that minor into the licensed premises of a cultivation facility, products manufacturing facility or cannabis testing facility in an emergency.