My family and I are planning to immigrate to the UK from South Africa this year.
My wife and I are both British citizens by descent through our fathers.
Our 2 children were both born in South Africa and their ages are 2 & 4. They cannot get british passports.
My wife and I have never lived in the UK for any period of time.
We have grandparents, brothers, cousins etc (All UK citizens) living in the UK who we could stay with without any issues as soon as we arrive.
What would be the best & cheapest visa choice for our children hopefully avoiding NHS surcharge etc if possible