Apps submitted under the Kids category face extra restrictions — no behavioral advertising, no third-party analytics without appropriate limits, and no linking out to non-Kids-category content or external purchases without a parental gate.
Frequently caused by a generic analytics or ad SDK bundled into a kids' app without checking whether that SDK is actually on Apple's approved list for child-directed apps.
"Your app is designed for kids but includes third-party analytics or advertising software not approved for use in Kids category apps, per guideline 1.3."