User blog comment:Bastian77/OVA5 Subbed Version Out!/@comment-70.30.71.208-20130618195938/@comment-7418318-20130618203441

Depends on when an Exceed is considered an adult. Compared with the other Exceeds Happy and Charla don't really look like children, so maybe they are fully grown at 5.

In that case Lily might be as young as 12 (5 to fully grow, plus the seven years between his saving Jellal and FT going to Edolas) + the timeskip 7.