The Pennsylvania Superior Court vacated the defendant’s convictions for sexually assaulting a minor because the trial court erroneously permitted a staff member from the Philadelphia Children’s Alliance (PCA) to testify that it is common for child victims to “under-disclose” sexual abuse to PCA interviewers. The PCA interviewer testified on redirect examination extensively regarding how and why children disclose sexual assaults. The Court found that testimony to be improper under Pa.R.E. 702 and 42 Pa.C.S. § 5920, which governs expert testimony in criminal cases where the defendant is charged with sexual offenses. The Court upheld the trial court’s decision not to provide a “prompt complaint” instruction to the jury.