If, as we hope, your daughter is now fine with no lasting consequences, then all you could sue for is the *additional* medical costs incurred because of the delays in diagnosis: that is, for out-of-pocket costs you only incurred because of the misdiagnosis (costs you would not have incurred if diagnosed correctly earlier). Since a medical malpractice suit can be very expensive (you have to hire  a medical expert to write a report and testify, and such experts can cost thousands of dollars), unless the medical costs are very large, it would not be worth suing. If there was a lasting harm to your child, then it is a very different story and you should speak with a medical malpractice attorney to explore your options.