Appeal of TPR and placement

We are in Northern California, and Completed adoption on one child age 2, mother has another half sib and we get placement of that child at 1 day from the hospital. Bio mom has lost a bunch and this is #5. Services terminated in September and then an aunt shows up and starts Relative assessment, goes to a .26 recently and the court does the TPR and rules out aunt who just recently completed and passed Relative Assessment. Mother appeals the TPR and also the placement. I understand that the TPR appeal is not unusual and bio mom would never get that reversed (I left out other things, just trust me on that part, the TPR is solid). However, the appeal related to placement is interesting. She is appealing the placement of the child and wants the child with the aunt even though the child is with an already adopted 1/2 sibling now. This child is now over 6 months and has only been with us. I can't see any reason why the appeal would be successful. First, I never knew the bio mom could appeal the placement. Second, I'm thinking the appellate court would not overrule the lower court because the law was followed. Just because a relative passes the relative assessment does not mean that they get placement. So we probably have very little to worry about other than how long the delay will be. Am I missing something?