May a parent track their 12- or 16-year-old's phone?

Dutch law uses a 16-year age threshold for digital consent (UAVG Art. 5). Under 16: parent with parental authority may install tracking app (Life360, Find My, Google Family Link), provided: (a) transparent — child knows, (b) proportional — not 24/7 surveillance, (c) child's best interest as motive (safety, not control). Dutch SC + ECHR jurisprudence: even within family, ECHR Art. 8 (right to private life) applies. 16-17 years: only with the child's own consent — it's their digital legal capacity. Forcing can be criminal (stalking Art. 285b in extreme cases). 18+: adult, no parental-tracking mandate. Two specific contexts: (1) Co-parenting/divorce — other parent tracking child without other parent's consent = often conflicts with custody arrangement (Dutch Civil Code Book 1). (2) Sharing location data with third parties — e.g. school or clubs — requires separate consent. Practical rule of thumb: can child practically see? Then make transparent. Covert = not OK. On violation: Veilig Thuis can help with family conflicts. On relationship-control by ex-partner via shared child = often red flag for stalking — call 0800-2000.