F v M & Anor: Jurisdiction

Facts

P is a little girl born in England in August 2024, who holds United States, Lithuanian and British nationality. Her mother, M, is a dual Lithuanian-United States national who pursued a ballroom dancing career across the USA, Germany and Spain; her husband SF, an American national, worked between London, the USA and Dubai. During a rocky patch in that marriage M began a relationship with F, whom she met at a dance class in March 2023; the relationship ended by February 2024, after M discovered she was pregnant. F is not named on P's birth certificate and has no parental responsibility; SF acquired parental responsibility by a Step-Parent Parental Responsibility Agreement made on 24 March 2025. In February 2025 F applied urgently for a prohibited steps order, asserting a risk that M would leave the country; that application was refused and highly contentious litigation followed, including an interim contact order made by District Judge Hughan, a variation before Recorder Brannan, and a successful appeal by M and SF before Mr Justice Poole. F sought a declaration of parentage, parental responsibility and orders to spend time with P; M sought permission to relocate P to the USA. Shortly before a dispute resolution hearing listed for March 2026, M applied for a declaration that P was no longer habitually resident in England and Wales, so that the court lacked jurisdiction. That application came before this court.