A more thorough explanation:

Paternity presumption is a legal concept in family law that assumes the identity of the father of a child. It is based on certain circumstances that create a presumption of paternity, even if there is no biological proof of the father's identity.

There are three situations that can create a presumption of paternity:

• The man is married to the child's mother when the child was conceived or born, even if the marriage is later found to be invalid.
• The man marries the mother after the child's birth and agrees to have his name on the birth certificate or to support the child.
• The man welcomes the child into his home and later holds out the child as his own.

For example, if a married couple has a child, the husband is presumed to be the father of the child. Even if there is evidence that the husband is not the biological father, the paternity presumption still applies.

Another example is when a man marries a woman who already has a child. If the man agrees to support the child and puts his name on the birth certificate, he is presumed to be the father of the child.

The paternity presumption is important in determining child support, custody, and visitation rights. It can also affect inheritance rights and other legal matters related to the child.