Sorry to hear you've been ill.
You may wish to check with a French or Maurtian lawyer to see if there is any provision by which French Overseas citizenship can be passed to them. I cannot advise in this respect, being a UK qualified lawyer.
Under our immigration rules they are not eligible for UK citizenship at present, this can only descend one generation to person born outside of the UK. This has already happened, to your daughter.
However, I believe they may be eligible to apply for an ancestry visa so that they can come and work here. The eligibility criteria is as follows, she will have to show that:-
- you are a Commonwealth citizen; (passport)
- you are aged 17 or over; (passport)
- you have a grandparent who was born in the UK (including the Channel Islands and the Isle of Man), or a grandparent who was born before 31 March 1922 in what is now the Republic of Ireland; (statements from them, statements from you evidence of your UK citizenship (passport)
- you are able to work and you plan to work in the UK (statements, job offer or evidence of jobs they could do)
- you can adequately support and accommodate yourself and your dependents without help from public funds (financial evidence, banks statements, etc)
Once they have worked in the UK for 5 years they will be able to apply for indefinite leave to remain and 12 months after receiving ILR, UK citizenship. Once they have this they can obviously apply for a UK passport.
They should contact their nearest UK embassy and ask for the forms for an ancestry visa and begin collating their documents 3 months before they intend to travel.
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