Apparently the mother involved wants to send her younger child to the school she finds so unsatisfactory in September. I don't think this is reasonable. I understand the logic of leaving a child at a school where they are established, but she should be expected to find a school she likes better for a younger sibling, surely.
She also intends to bring another suit, presumably tax payer funded again. I think that she should be expected to pay in full for any further suit she brings against the school. She could apply for costs if she wins.