Judgment of the Court (Fourth Chamber) of 18 December 2025.#SM and Others v Caisse pour l'avenir des enfants.#Requests for a preliminary ruling from the Cour de cassation du Grand-Duché de Luxembourg.#Reference for a preliminary ruling – Article 45 TFEU – Freedom of movement for workers – Equal treatment – Regulation (EU) No 492/2011 – Article 7(2) – Social advantages – Family allowance – Condition for granting that allowance to a non-resident worker for a child of his or her spouse or registered partner – Requirement that that worker must ‘support’ that child – Assessment criteria – Presumption based on the existence of a joint household – Directive 2004/38/EC – Article 2(2)(c) – Concept of ‘family member’.#Joined Cases C-296/24 to C-307/24.