Does this make any sense whatsoever??!! ok, I'm going to surprise you:
Yes. It makes sense.
Stinks for D12, but it is a growing opportunity. It is something she can address personally. She can now take more responsibility for herself.
It's not pleasant to be suspended, but D12 will learn from this. She'll learn to be responsible for this part of herself. I don't want to be an old meany, but I do not agree that this is punishing D for something she has absolutely no control over. The fact is that the school has rules and the principal cannot bend them. The principal has no control over the kid's father. A lesson you learned for yourself, I think. It's not as if it is prison for the kid. It is serious for a schoolkid, but come on, keep perspective. It's not the end of the world. It's not cruel and unusual. The kid has a chance to learn through this.
And YOU can coach her through it. YOU can be the one to help turn this negative into a teaching/learning opportunity. (High five!)
No need to be angry. No need to be indignant about H's behavior.
HM: How was suspension?
D12: Dumb. It was boring and I hated it.
HM: Being late means suspension.
D12: Yes, I know, and I hate it and blah blah blah.
HM: (Active listening) You don't like to be late. Suspension stinks. You'd rather be at home watching your show, hanging with friends, whatever.
D12: Yes, and Dad makes me so mad, etc etc etc.
HM: You don't like it when he brings you to school late. You feel like he should have gotten you to school on time.
D12: Yes, and blah blah blah (more of her perspective).
(this active listening part can go on longer than you might expect. And it may be longer than feels normal or healthy. But that's ok. Let her complain about it, and just reflect back what you are hearing. you must resist the urge to solve her problem, and absolutely resist the urge to get her to stop complaining. After enough expressing herself, she will understand that you understand her. Score! Major mom points there! ok, then there will be a pause... then....)
HM: What do you think you could do about it? What can you do to avoid being late in the future? (implicitly put responsibility on her)
D12: Well it's dad's fault and blah blah blah (if she is true to form she will duck the responsibility.)
HM: So you feel like your father could have avoided this.
D12: Yes and he was wasting time, just watching TV and (more complaining and putting it all on dad).
HM: I can see you are really unhappy about this. So what do you think YOU can do about it?
(D12, if she is a normal kid, will mull this over. Not sure what to make of it. She may try to avoid it again. Don't let her. She may want to complain some more. That's fine. Listen. When she tries to blame her father, push back)
HM: You really feel like your father should do this, but he just isn't doing it for you. What can you do? Did you tell him you needed to be on time?
D12: YES! I told him a million times!
HM: Ok, that didn't work. What else might work? Do you have any ideas?
At this point wait for her. Let her figure it out. Don't give her the answers. The key point is not to solve this immediate challenge (being on time). The key part is to teach her to solve her problems on her own, even when they are awkward situations, even when she wants someone to just save her. She needs to find her own path to power, even when she is disadvantaged or feels like she is not empowered. This is a really cool thing for a 12-yr old girl to start learning and practicing.
She may ask you for ideas. That's great! But don't give in too easily. You will be surprised at the cool solutions she can come up with.
She may ask you to do stuff. She may ask you to talk to her father on her behalf. Do it. Maybe invite her along. Focus on the lateness. No blaming. Resolve the conflict. Stick to business.
She may ask you to do other stuff. Do what you can if she asks for help.
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It's ok. Part of growing up. You didn't want this. She didn't want it. But she'll be ok. In fact better than ok. You can make something really good out of this situation.