Because of where you are posting, I will assume you meant baptised in the Catholic Church.
Code of Canon Law
CHAPTER III : THE PERSONS TO BE BAPTIZED
Can. 868 ß1 For an infant to be baptized lawfully it is required:
1ƒ that the parents, or at least one of them, or the person who lawfully holds their place, give their consent;
2ƒ that there be a well‚founded hope that the child will be brought up in the catholic religion. If such hope is truly lacking, the baptism is, in accordance with the provisions of particular law, to be deferred and the parents advised of the reason for this.
ß2 An infant of catholic parents, indeed even of non-Catholic parents, may in danger of death be baptized even if the parents are opposed to it.
Single Parents often have their children baptised.
And I have to include this last on, so that we may always keep our most precious in the forefront of our minds.
Can. 871 Aborted fetuses, if they are alive, are to be baptized, in so far as this is possible.