It's an interesting thing working with younger actors. As a person who was once young herself, I believe kids need free time to spend just hanging out with friends or reading or shopping..., but as a teacher and a parent i also know the importance of teaching kids about honouring commitments, not over-committing, managing time, managing relationships etc. Skills that will be needed more and more as they get older.
My response to the actor was two-fold:
Make a phone call to the director explaining what has happened (NOT A TEXT OR I.M. OR P.M. OR ANY SUCH BRIEF TEXT-BASED IMPERSONAL COMMUNICATION WHICH ALLOWS ONE TO AVOID THOSE AWKWARD MOMENTS WE SOMETIMES HAVE TO FACE). The director had worked hard to create an ensemble role for this person as she believed in the actor's value (due to the actor advising up front that there was a large chunk of time where they would be unable to attend rehearsals close to production dates they could not be cast in a lead) . I explained that this personal explanation and apology was a mark of both character and respect, and would go a long way.
I then went on to explain that both amateur and professional companies run black lists of a sort. In Australia our industry is not huge and people talk to each other. If an actor has created a reputation in a show for being difficult or not turning up to rehearsals or suddenly pulling out of shows etc., it can effect their ability to get work.
This actor had specific reasons for having to pull out of the show and did offer to help out backstage during the production, which I appreciated. However, I have known this young person for a long time, and know them to be a decent person, talented and hardworking. The thing is, not everyone on this production knows the actor that well yet, and they will talk. Not in a malicious way. It's just, people talk. As it stands, this actor has not yet called the director and it is impacting the desire of some people within the company to work with this person in the future.
I certainly speak up for second chances, but that won't always be enough.