Children born in Belgium can assume Belgian nationality only if the parents have lived in Belgium for at least five consecutive years in the ten years prior to the birth or if one of the parents has been allowed to remain indefinitely in the country. If that is the case your child can be granted the Belgian nationality on the condition that you submit a request for Belgian citizenship before he/she reaches the age of 12. If that is not the case, children will normally assume the nationality of their parents. If the parents have 2 different nationalities, the best is to check with the CGRA as your refugee status does not allow you to have any contact with the embassy/ consulate of your country.
A child will also receive the Belgian nationality if not granting the Belgian nationality would render the child stateless. For more information:
https://justice.belgium.be/fr
https://www.angloinfo.com/how-to/belgium/brussels
https://diplomatie.belgium.be/en/services/services_abroad/registry/registration_certificates