a child born to Brazilian citizens abroad is a Brazilian citizen.
A person born outside Brazil of a Brazilian parent also acquires Brazilian nationality at birth if:
1) The Brazilian parent is in the service of the Brazilian government; or
2) The person is registered with a Brazilian consular office; or
3) The person later moves to Brazil and confirms one's nationality before a federal judge.
https://www.msn.com/en-us/news/us/2-year-old-us-citizen-deported-to-country-where-she-lacks-legal-status/ar-AA1FNic0?ocid=hpmsn&cvid=aef5ecac415d4fc3b65d660c7d52ee6f&ei=84