Unless a court excludes a man as the father of a child, a man is the father if: the man was married to the child’s mother at the time of the child’s conception; the man was married to the child’s mother at the time of the child’s birth; the man is named as the father on the child’s birth certificate and has not signed a denial of paternity; the child’s mother has named the man as the child’s father and the man has not signed a denial of paternity; the man has been adjudicated to be the child’s father; the man has acknowledged himself, orally or in writing, to be the child’s father and the mother agrees; or on the basis of genetic testing, the man is indicated to be the child’s biological father. A petitioner under this subtitle shall give a court notice that a man who is not named in the petition and has not been excluded as a father claims paternity. After a request of a party or claimant and before ruling on a petition for guardianship or adoption under this subtitle, a court shall hold a hearing on the issue of paternity.