Research Institute of the McGill University Health Centre (K.M.), Montreal, PQ; Division of Child Neurology (K.M.), Department of Pediatrics, Montreal Children's Hospital, McGill University, Montreal, PQ; Department of Neurology & Neurosurgery (K.M.), Montreal Children's Hospital, McGill University, Montreal, PQ; Child Neurology and Psychiatry (C.M.), Salesi Pediatric Hospital, United Hospitals of Ancona, Ancona, Italy; Division of Genetic Medicine (G.L.C., J.N., H.C.M.), Department of Pediatrics, University of Washington, Seattle, WA; Department of Neurology (A.M.), Great Ormond Street Hospital for Children, London, UK; Developmental Neurosciences Programme (A.M.), UCL Great Ormond Street Institute of Child Health, London, UK; Neurology Network Melbourne (J.P.), Melbourne, Victoria, Australia; Murdoch Children's Research Institute (C.S., I.E.S.), Parkville, Victoria, Australia; Department of Paediatrics and Child Health (T.S.), School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand; Division of Neurology (S.M.), Department of Pediatrics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; Neurology Unit and Neurogenetic Laboratories (C.B., A.R., R.G.), Meyer Children's Hospital, Florence, Italy; Department of Clinical Genetics (R.H.S.), Great Ormond Street Hospital, London, UK; Epilepsy Research Centre (I.E.S.), Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, Victoria, Australia; Department of Paediatrics (I.E.S.), Royal Children's Hospital, The University of Melbourne, Parkville, Victoria, Australia; and The Florey Institute of Neuroscience and Mental Health (I.E.S.), Heidelberg, Victoria, Australia.