[blimp]

in many countries' legislation it is added that if the adult has/had reason to believe that the person he/she has engage with in a sexual act is/was above age of consent, he or she is not deemed to have done anything illegal. this can for instance be, the adult was lied to or the minor looked or in some way gave the appearance of being be of or above the age of consent.

the above is however not applicable to the poster's question since he/she seems very aware of the girl's age.

to the poster, be extremely careful since there seems to be some ambiguity whether age of consent is 13 years old or 18 years as it seems to be indirectly referred to in the child welfare law.