Sometimes the father of a child is unknown. A paternity test compares the DNA of a child, mother, and alleged father to see if the man is or is not the biological father of a child. Sometimes a judge also orders a DNA sample taken from other people, like grandparents, siblings, or other relatives. Usually, the DNA is taken by swabbing the inside of a person’s cheek. It must be done by an expert. "At home" kits will not be allowed.

If you request a DNA test, you may have to pay for it. You can also ask the judge to split the cost between you and the other party. If you have a fee waiver, you can ask the judge to let you not pay.

In Illinois, a man is presumed to be the father of the child if genetic test results show that he is at least 1,000 times more likely to be the child’s father than a random man. Be sure to ask the judge to enter an order of paternity, and get a copy of it.