Yoram Hirshfeld, 78, and his daughter, Noga Hirshfeld, 40, a Cambridge physicist, were killed, and a young girl of primary school age suffered serious injuries and is in a serious but stable condition in a London hospital.
A man in his 40s and a boy of primary school age sustained minor injuries.
Nitesh Bissendary, 30, of Highlands Glade, Manston, Kent, has been charged with two counts of causing death by dangerous driving, two counts of causing serious injury by dangerous driving and assault occasioning actual bodily harm.
He has also been charged with failing to stop at the scene of a road traffic collision, drug driving and failing to provide a sample for analysis, and will appear at Folkestone Magistrates’ Court on Saturday.
Officers investigating the incident also arrested a 58-year-old man and a 55-year-old woman on suspicion of assisting an offender and possession with intent to supply class A drugs, and both have been released on bail until September 8.
Kent Police said inquiries are being carried out by officers from the serious collision investigation unit who remain keen to hear from any witnesses, local businesses with CCTV evidence or drivers with relevant dashcam footage.
They are asked to call the appeal line on 01622 798538 quoting reference DS/DGC/090/22.
A vigil was held on Thursday evening on Leopold Street to pay tribute to the family who were on holiday in Ramsgate.
Friends of Mr Hirshfeld, a former mathematics professor at Tel Aviv University in Israel, have spoken of his kindness.
Tributes have also been paid to Ms Hirshfeld, also known as Noga Sella, who was a girl guides leader with 2nd Milton Guides and Milton Rangers in Cambridgeshire.