I think this would be a normal choice you have to confront your daughter with, regardless of whether you have the divorce/split-time issue involved. You have a 2 year old and another on the way. Your daughter cannot expect that you have the time to shuttle her to all the practices and tournaments, etc. I can see why the mom thinks she should "fully support" her daughter since sports is a positive thing, but there are also other positive things to teach a child. I agree with you that making tough choices is something all people should make.
I would say that your terms were reasonable, you communicated them clearly, and stick to your guns. Since your daughter is understanding of the situation, just keep reminding her of the great time she had during the Fall Ball. Dealing with the contradiction/under-mining from the mother and inconsistent treatment from the coach is another issue. Ideally, you would see eye-to-eye on everything, but that isn't the case and it's doubtful you'll convince her to be consistent with you and your husband. Just try to keep it clear to your daughter that families have different rules and she needs to respect them. It's unfortunate that she has to deal with 2 homes with 2 sets of rules/values, but just try to help her see the value in BOTH of your opinions.
It doesn't sound like mom had another child? It also sounds like softball is a social thing for the mom and stepdad, which means having the daughter sit out All Stars is asking *them* to sit out on their social calendar as well. They might be unhappy with that, not just the whole "how dare you ask your daughter to sit out on something she loves."I think that would be a very subconscious thing though.
Is there a middle school team your daughter can participate in that would be less of a time drain?
Just my 2 cents.
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This is partly in response to Toni's post.
I don't think this is a purely "my divorced kid is suffering because of *my* choices" situation. This *is* how the situation is framed, which complicates things for your daughter. That's why I suggested that you need to talk to the step-daughter about these different values so she understands these different rules/points-of-view.
There were plenty of times my family had to sit down to talk about activities, how much time my parents had to drive us around, and what was reasonable for them. My parents were not divorced, they both worked, and sometimes my dad had to work 2 jobs. Traveling to games, staying in a hotel every other weekend? With a toddler and newborn? Whether this is a blended family situation or not, that's a lot to take on as a parent OR step-parent, and I don't think it's unreasonable to sit down with a child and say, "This is very hard on me. I hope you understand." Time is just as precious as being able to "afford" something, so just scoffing the cost is not helpful.
If the girl's mom *does* have a toddler and infant and still has time and energy to shuttle her daughter to all softball all day, then hats off to her. I think if this is the same decision you would make if this were not a blended family situation and she were your own daughter, then put your mind to rest.