N and S (Habitual Residence), Re

Facts

The applicant mother (M), a British national serving as a senior diplomat, and the respondent father (F), a dual British and American national, are the parents of two boys, N (12) and S (10). The children were born in England and lived here continuously until 19 September 2025, when the family moved to State A at the commencement of M's four-year posting, due to run until September 2029. The move initially went well, but in December 2025 the relationship broke down. M alleged that F had assaulted her; an FCDO investigation into events on 22 December 2025 concluded only that an altercation had likely taken place, and F was required to leave the FCDO platform in State A. F, for his part, alleged that M had abused alcohol for years, producing extensive statements, journal entries recording her drinking, and covert recordings both of M when inebriated and of a 50-minute conversation with N. M countered that F had distorted her drinking to gaslight and control her. On 16 February 2026 M applied for the summary return of the children to State A under the 1980 Hague Convention, the children having left State A on 2 February 2026. The central question was whether the boys had acquired habitual residence in State A.