If you do give up your Brazilian Citizenship: as with Russia and Italy who will want proof that the baby is stateless before giving citizenship to your baby, the UK will also be in the same camp. You'll probably have a field day convincing any one of them to make the first move.
This is one of the points I raised a long time ago.
Have you heard of effective nationality? It is a principle of private international Law.
I have taken this from application form S" for stateless persons:
1.25 Details of Applicant’s Father
1.26 His full name:
Richard66
1.27 Date of birth
XX/XX/XX
1.28 Place and country of birth:
XX, Brazil
1.29 Nationality when the applicant was born*:
British citizen by descent
1.30 Present nationality:
British citizen
*(If a British citizen, a British overseas territories citizen, a British Overseas citizen, or a British subject, state how this status was acquired e.g. by birth, adoption, descent, registration or naturalisation. If by naturalisation or registration please give the date and number of the certificate and place of issue.)
This is all that is asked of me, the father. I do not believe that, legally speaking, I am withholding information or that, indeed, I can give any more. Remember, if I had been born in Italy I would stiull be British by descent but I would
not be Italian.
I think at this point I need to consult a specialised lawyer.