ICA’s answer explained
Bring physical/digital IC and the current passport if it was valid when applying. For a child under 16 at application, bring the original/digital birth certificate, consenting parent’s IC and current passport if applicable. At ICA only, an alternative accompanying adult also brings their IC and the consenting parent’s signed authorisation identifying both adults and the child.
Official ICA source
Written independently from ICA’s English original. The linked source supplies the complete document and subsequent updates.