Have you tried a delayed or early entrance when it is quieter? ASD/ADHD present differently in girls and their ability to mask will allow them to appear ‘fine’ once they are in school. Have the teacher look at their placement in classroom – could be she isn’t speaking up about something bothering her there, or at a particular time of day that she is trying to avoid. Some children hate lunch, breaks, are afraid of/triggered by member of staff? Worth exploring with a staff member she trusts; not always the pastoral care lead.