Here is the email I sent.
Dear XXX
I thought I'd let you know that we have finally discovered why Eileen is refusing to come along to dance class. It seems that much as she loves her lessons she is upset as no-one wants to be her partner.
I realise that Eileen is a bit of an urchin but she is a kind and thoughtful child and has found this hurtful.
I do understand how children behave, especially girls as I have two daughters, I would just like you to be aware of the reason behind Eileen's reluctance to attend further dance lessons.
Regards Hester
Here is what I wanted to send.
How dare you let those little bitches be so unkind to Eileen!
Let me at them and I'll have their guts for garters!
See I can be tactful when necessary, hubby didn't believe me, he wanted to read the emails before I sent it!