AZ state child custody laws, proceudre for appealing child custody decision

My niece has been primary custodian since her son was born. The child has had visitations with his father, but is closer to his mother. The court’s own expert witness testified that the mother should be awarded custody for many reasons. But after the custody trial, the judge awarded custody to the father, without providing any legal reasoning or justification for this decision. The child is traumatized and cries to stay with his mother. The judge had only been on the bench a few weeks. What recourse do we have for immediate review of this legal decision? The appeal process takes a long time, and a week is a long time in the life of a four-year-old.