Haha JKS we overlapped there with completely opposite advice.
My reason for suggesting restraint for now is - if she has a valid reason for not being there (which we don't know), she is just going to feel worse if you point out to her that her valid reason was not acceptable. If D13 can handle things for now, let her do that. Earlier I think you mentioned you didn't necessarily trust D13 to put the girls to bed as you would like them to be put to bed? Maybe this is a good way to learn to step back a little and let D13 show she can be responsible here (if you already trust her, which you said you do).
////Again, though, I don't have kids, so I'm not an authority on this by any means when it comes to dealing with them and which kid watches which.
