ETA: okay, Your daughter is MAYBE starting to be friends with Kasey.
Probably because, you drive those kids and sometimes pick them up.
Your daughter, is not friends, with Allie. Kasey, is her possible friend, and possibly "bonding" with her.
Your daughter, needs to have her OWN friends. NOT it being based on, the sibling of that friend, ALWAYS having to be there too.
You do NOT have to invite, Allie over. Realize, that.
And they do not all have to be friends... just because you drive them all around.
ALL kids, will have friends at some time or other, that also have siblings. That does NOT mean, that every time your child... has a friend with siblings, that you HAVE to invite the siblings over, too. You don't. You invite your child's friend. A child, needs to learn, that they have their own friends. And that is life.
My kids have lots of friends of their own. Their friends, many of them, have siblings. But I don't invite, ALL their siblings over, too. I invite, MY child's friend. It is not a package deal. And just because one of my kids may have a play-date, it does not mean that BOTH of them have a play-date. Sometimes, only my son has his friends over. Then other times only my daughter has friends over. And it does not include, their friends siblings, too. It is THEIR friend or friends, that come over.
Kids need to learn that. And as a child gets older, they don't want their siblings tagging along. They have their own, socials.
And I HAVE told the other Moms, "only your daughter....:" or "Only your son.... this time.... The kids need their own time with their friend. No siblings." I say, it. And the other Moms do too. They UNDERSTAND.
Your other problem is: you pick up and drive those girls to and from school. But you do NOT have to do, that. You choose to. Thus, your kids and those kids, are getting all bunched up together. By default. You do not have to drive those kids around. But you do. And those kids, and their Mom, can have their Grandparent do the driving of those kids. It is not your, job.
And the other problem is: KASEY "everyday this week" has been begging and begging to come over. Well, just say no. You want those girls to bond? Your daughter and her??? Why?
Does your daughter, like Kasey? Teach your daughter how to choose friends. And besides, in school, kids make friends. Kasey is not the only kid. There are other kids in school. And you don't have to car-pool or drive other parent's kids around, just to have friends for your kid.
And you teach your daughter, that YOU decide.
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Just say NO.
And you do not have to drive them around. Nor babysit them.
I used to have 2 siblings over at my house after school, and drove them home etc. The Mom is working/busy. has long hours, etc. Fine.
But ya know, one day I just got fed up. One of the kids is icky and never listens. And I just told the Mom, NO more.
Having a bunch of kids, her kids over, after school on a weekday is TOO busy. And I just don't want to.
I am not her kid's babysitter. Nor am I a cafeteria. Nor am I a shuttle driver.
Nor am I an after-school Aide who ALSO has the kids do their homework before their Mom picks them up.
And I TOLD my kids NO more. Having those kids over is too much of a pain. And we are too busy and *I* just want our own space and quiet and our OWN routines, after school, after coming home. And MY kids have their own activities AND homework and responsibilities to do, after school.
That's it!