AB v EM  EWHC 549 (Fam) concerns for a large part the application of Brussels IIa’s traditional jurisdictional rules (habitual residence etc.) and I shall not comment on those.
Of interest to the blog are, first, at 37 ff the application of the Regulation’s forum non conveniens rules: in that respect, compare with my posts on V v M and W v L. Further, the question whether the order made by the Sunnite Sharia Court of Beirut on 6 February 2019 in proceedings commenced by the mother in Lebanon in November 2018, incorporating and approving an agreement between the parties to these proceedings regarding custody and access with respect to M, capable of recognition in the UK and, if so, what impact should this have on the UK courts’ welfare determination? The 2019 agreement established that the father would have custody of M and would reside with M in either the United Kingdom, Egypt or some other location of his choosing.
MacDonald J at 71-73, having referred to the spirit of comity, does not hold on what at 73 are briefly refered to as ‘wider criticisms’ of the February 2019 Order, or the allegations of durress in the coming to be of that order. He notes more as a matter of fact that circumstances in the child’s welfare have changed since the Order, and that the father did not at any rate honour elements of the agreement which the Order had confirmed.
No grand statement of principle, therefore. Rather, a measured practical approach.