I will ask the reason for why he didn't attend the rehearsals. then i would say my group to be patient.if he gives the correct reason then its okay.otherwise , i would give my advice as follows:
* please avoid bunking the rehearsals.
*you a group member of our dance.if you don't perform well our whole dance group will get a bad remark.
AT LAST ....
*please say if you are not interested.
Sana- Hi Kritika Do you know today again Nancy did not attend the rehearsals today also.
Kritika- It is difficult to make her understand but You should go and clearly tell  her that she should attend that rehearsals as it is important for her.
Sana- Yes I did that but she told that she is not willing to practise dance with us.
Kritika- But in a group dance it is very important to practise the dance steps otherwise she won't be able to coordinate with us.
Sana- Yes I will try again to advice her and make her understand that she needs to rehearsal with us.
Kritika- If she doesn't take it seriously we will complain to our dance teacher to replace her with any other girl who is willing to take part.
Sana- Yes, you are  right Kritika let's go.