Since at least the 1950s, and possibly earlier, the policy on British citizenship by descent has been that British citizenship can be automatically inherited only one generation outside the UK.
A British citizen otherwise than by descent (so, by birth in the UK to British citizens or people on ILR, by naturalisation in the UK or by registration under certain specific sections) can automatically pass on their British citizenship to children born outside the UK or its overseas territories.
A British citizen by descent can't
Any child born to you, a naturalised citizen, within the UK or any of its overseas territories, such as the Turks and Caicos Islands or the British Virgin Islands, would be a British citizen otherwise than by descent.
Any child born to you, a naturalised citizen, outside these places would be a British citizen by descent. They will be able to enter and live in the UK as a British citizen. But their children born outside the UK will not be British citizens automatically.
Any children born to them within the UK or its overseas territories will be British citizens otherwise than by descent, as those children will have been born in the UK to a British citizen (whether by descent or otherwise is immaterial if the child s born in the UK)
So, to sum up, the only difference between a British citizen otherwise than by descent and a British citizen by descent is that the latter can't
automatically pass on British citizenship to their
children born outside the UK.
So, in your case, your grandchildren through your elder child born in the US will be British citizens by descent (because your elder child was registered as a British citizen), but any children born to your younger child in the US will not automatically be British citizens.
Under certain specific circumstances, the British citizen by descent can register their children as British citizens, but that is the furthest that British citizenship can be acquired by descent if they are born outside the UK.
To clarify further on certain points mentioned by
@alterhase58 above,
alterhase58 wrote: ↑Fri Oct 27, 2023 10:46 am
a child born to her/him in the UK (after parent had three years residency, I believe) will be a "British Citizen Otherwise than by descent".
It is slightly more complicated than that.
If the British citizen by descent parent has completed three continuous years of residence in the UK
before the birth of their child abroad, they can, subject to other conditions, be registered as British citizens (i.e. they are
not automatically British citizens). AND even in this case, the child would become a British citizenby descent themselves.
On the other hand, if,
after the child's birth outside the UK, the British citizen by descent parent moves to the UK with the child AND other parent for a period of three continuous years which complete before the child's 18th birthday, then the child can be registered as a British citizen and in this case, the child would be a British citizen otherwise than by descent.
None of this hassle applies of course if the British citizen by descent's child is born in the UK or its overseas territories. It is specifically only if the child is born outside these territories to a British citizen by descent.
alterhase58 wrote: ↑Fri Oct 27, 2023 10:46 am
The passport would state "British Citizens by descent".
That is not correct. A British passport issued to a British citizen, whether by descent or otherwise, would just state "British citizen".
The UK does not have citizenship registers, unlike some European countries. The only way to prove the method of acquisition of British citizenship (which determines whether the person is by descent or otherwise) is by presentation of original documents (such as a naturalisation certificate, British birth certificate with parent's ILR BRP, etc) when applying for the first British passport, or at any other time, if asked for by an appropriate authority.
The onus is on the applicant and/or their parents to preserve the documents and present them as required.
Your naturalisation certificate will be the basis of not just your younger child's British citizenship, but also any of their descendants, who may be asked to prove their descent from a British citizen otherwise than by descent ancestor.
Your elder child's proof of British citizenship is their own registration certificate, but their descendants may also need that certificate for the same reason as above.
On a separate unrelated note, be aware that the UK is moving towards a more residence based system for accessing benefits and other social programs. So, for instance, to access student financing, there are specific residency requirements that apply even to British citizens.
A British citizen, whether by descent or otherwise, can't just fly in and access all social programs, whether they be the state pension or student financing.
I am not a lawyer or immigration advisor. My statements/comments do not constitute legal advice. E&OE. Please do not PM me for advice.