1. Look for birthmarks, moles, or other physical traits that you share with the child. If there are none, it is possible that the mother had children from another man before she met you.
2. Pay attention to the child’s personality and behavior. Children can inherit their father’s characteristics, including temperament and interests. For example, if you share a passion for sports or music with your partner’s son or daughter, then it is possible that he or she is biologically related to you.
3. Ask questions about the child’s medical history. There may be patterns in his or her health that could reveal information about the child’s parentage. For example, if you are both insulin-dependent diabetics, then it is possible that your child shares this trait because he or she also has diabetes.
4. Look for documentation of paternity. In many cultures and countries, keeping a detailed family tree is important. While you are living with or dating the mother of your child, ask her if she has documented proof that you are the father. If she does not have any such documentation and still refuses to take a DNA test, it could indicate that there is another man who may be raising your child.
5. Consider whether the child is financially dependent on you. If your partner has not worked or has financial difficulties, it is possible that she had another partner before meeting you. In these cases, if the other man is raising your child, he may be providing economic support for the mother and therefore the child through welfare payments or similar programs.
6. Discuss the situation with your partner to determine when and how often she might have engaged in sexual activity outside of your relationship. It is possible that if she had sexual relations with other men while you were dating, the child may be the product of one or more of these relationships. If your partner was having multiple relationships at once, then this increases the likelihood that your child has a biological link to you.
7. Speak to an attorney who specializes in family law. He or she can provide advice about your legal options for establishing paternity. For example, if the child’s mother does not want to take a paternity test, an attorney may be able to help you obtain a court-ordered DNA test.
I’ve always been interested in DNA testing and genealogy. My DNA testing research is approved by my teachers at the Boston University of Genealogy. I’ve been following DNA testing’s rise since its first appearance in 2006.