Opinion of Advocate General Pikamäe delivered on 14 July 2021.#A v B.#Request for a preliminary ruling from the Korkein oikeus.#Reference for a preliminary ruling – Area of freedom, security and justice – Jurisdiction, recognition and enforcement of decisions in matrimonial matters and the matters of parental responsibility – Regulation (EC) No 2201/2003 – Scope – Article 2(11) – Definition of ‘wrongful removal or retention of a child’ – Hague Convention of 25 October 1980 – Application for return of a child of a young age whose parents have joint custody – Third-country nationals – Transfer of the child and his mother to the Member State responsible for examining an application for international protection under Regulation (EU) No 604/2013 (Dublin III).#Case C-262/21 PPU.