"x x x.
As a rule, illegitimate children shall use the surname of their mother.
The only exception to this is if the filiation of the illegitimate children has been expressly recognized by their father through the record of birth appearing in the civil register, or when an admission in a public document or private handwritten instrument is made by the father, in which case the illegitimate children may use the surname of their father (Article 176, Family Code of the Philippines, as amended by Republic Act [R.A.] No. 9255).
In the situation of your child, he is already using the surname of his biological father.
We can only surmise that this is for the reason that you registered him under his father’s surname in view of the recognition that he made of your son in the latter’s birth certificate.
Thus, your son will be identified with his given name as appearing in his birth certificate until the proper court says otherwise.
Now, to seek for the change of the entry of your child’s surname as appearing in his birth certificate, we submit that neither you nor his biological father has the right to institute the same.
Such discretion is left to your child alone.
Thus, demanding from your child’s biological father to help you change the latter’s surname to that of your surname is useless, because his cooperation or decision over the matter will not be given weight by the court.
To reiterate, it is the child’s decision that will be taken into consideration not that of his parents.
This is in line with the ruling of the Supreme Court in the case of Grande vs. Antonio (G.R. No. 206248, February 18, 2014), which states:
“x x x Art. 176 gives illegitimate children the right to decide if they want to use the surname of their father or not. It is not the father (herein respondent) or the mother (herein petitioner) who is granted by law the right to dictate the surname of their illegitimate children. x x x”
Insofar as the custody of your child, the right is granted to you pursuant to Article 176 of the Family Code, as amended by R.A. No. 9255.
However, your child’s biological father may seek for visitation rights provided that he can establish that the grant thereof will be beneficial for the welfare and total upbringing of your child.
x x x."