In Bitcoin Ordinals, a "parent-child inscription" refers to a mechanism where one ordinal inscription (the parent) can be linked to another ordinal inscription (the child). This concept enables hierarchical or related structures of inscriptions, allowing for more complex use cases like collections, provenance, or dynamic data linking within the Bitcoin blockchain.
This system creates a clear on-chain provenance, showing that child inscriptions come from the same owner as the parent. It allows for trustless tracking, meaning relationships and authenticity can be verified directly on the blockchain without a third party.