Advice for children turning 18 and not in UK

Hi there,
we qualify to apply for naturalisation as citizens after ancestry visa and now ILR. we have 2 children who are currently 11. My question is - if we leave the UK in the next 3 years what will happen when the children turn 18? Will they automatically qualify as adult citizens under the category that their parents will be citizens 'otherwise than by descent'? Or will there be an issue with the fact they will not have lived in the country for a few years?

any advice will be greatly received.

cheers

If a parent is applying for naturalisation, then the children, who are not automatically UK citizens at birth, should apply for registration as well.

Thanks Vinny, yes we will be applying for them as child citizens now. But what happens when they turn 18 and haven't lived in the UK for 5 years?

Nothing should happen. If the children register as British citizens now, then they will continue as British until they renounce or are deprived.