Requesting a birth certificate of someone born in Belgium presents some hurdles that are not present when making such a request in the U.S. That's because the European Union, which Belgium is a member of, has much stricter privacy laws regarding personal information than the U.S. However, this doesn't make such records requests impossible. As long as you are a direct family member of the person for whom you are making the request, your request should be honored.
Locate the municipality in Belgium where you want to make the records request.
Visit the municipality's website to get its mailing address, and other contact information, if necessary.
Write a letter to the proper authority within the municipality. This will vary from jurisdiction to jurisdiction, but it will likely be the Town Hall or the Civil Registrar. You can find the proper authority on the municipality's website or by calling the municipality's administrative offices. When you write the address, do so in the official language of the municipality. In Belgium, some jurisdictions may use Dutch while others may use French. Once again, check with the municipality to confirm.
Write your request. You may do so in English. Be sure to list the person's full name, birth date and location of birth if possible. Also, detail your relationship to the person as much as possible. If you do not, because of privacy laws, your request will likely be denied, unless the record is more than 100 years old.
Include payment for processing your request. This will vary from municipality to municipality but will likely cost around $10. Check with the municipality for details.
Wait one to two months for a response.