Me daughter is 18 on the day of the election. She has got her postal vote form which has to be in before her birthday. Therefore, is she not voting illegally as she is not 18 when she casts her vote?
Obviously, since she is allowed to cast a postal vote (assuming she hasn't been illegally entered on the electoral register) no. I presume her vote doesn't count as being "cast" until it's removed from the envelope and placed in a ballot box, so it doesn't count before any other voting paper.