NIHR University College London Hospitals Biomedical Research Centre, Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, United Kingdom; UCL Institute of Child Health, London, United Kingdom. Electronic address: n.schoeler.10@ucl.ac.uk. NIHR University College London Hospitals Biomedical Research Centre, Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, United Kingdom. Department of Genetics Environment and Evolution, UCL Genetics Institute, London, United Kingdom. Department of Statistical Genetics, University College London, London, United Kingdom. Molecular Genetics, University of Exeter Medical School, Exeter, United Kingdom. Department of Neurobiology, Harvard Medical School, Boston, MA, USA. Department of Neurology, Massachusetts General Hospital, Boston, MA, USA. Royal Children's Hospital, Melbourne, Australia; Murdoch Children's Research Institute, Melbourne, Australia. Epilepsy Research Centre, The University of Melbourne, Austin Health, Melbourne, Australia. Royal Children's Hospital, Melbourne, Australia; Departments of Medicine and Paediatrics, The University of Melbourne, Melbourne, Australia; Florey Institute of Neurosciences and Mental Health, Austin Health, Melbourne, Australia. NIHR University College London Hospitals Biomedical Research Centre, Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, United Kingdom; Epilepsy Society, Chalfont St Peter, United Kingdom; Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands. UCL Institute of Child Health, London, United Kingdom; Great Ormond Street Hospital for Children, London, United Kingdom; Young Epilepsy, Lingfield, United Kingdom. NIHR University College London Hospitals Biomedical Research Centre, Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, United Kingdom; Epilepsy Society, Chalfont St Peter, United Kingdom.