noun
stepparent and stepchild; stepparent-stepchild relationship
A formal or legal term referring to the relationship between a stepparent and stepchild, or the pair itself.
継親子関係を法的に認める手続きが必要だ。
Procedures are necessary to legally recognize the stepparent-stepchild relationship.
彼らは継親子だが、実の親子のように仲が良い。
They are stepparent and stepchild, but they get along like a biological parent and child.
A more common word for stepchild, but 継親子 is a formal compound for the relationship or pair.
Compound of 継 (step-, foster) and 親子 (parent and child). The reading けいしんし follows on'yomi for the first two characters and kun'yomi for 子, a common pattern in formal Sino-Japanese compounds.