If you just want to know for your own purposes at this point, then no one needs to know about it but you, assuming you have periodic access to your son. I think they literally sell DNA testing kits at Walgreen's now. You buy the kit for maybe thirty dollars, then get the samples taken, which just involves running a swab along the inside of your and your son's cheeks, then mail them in with the testing fee (about another $100, I think). Within a few weeks, the samples will be compared and will yield a result that tells you whether you're the father. While doing it that way is cheap and easy, what it's not is admissible in court, because while the testing itself is perfectly valid, no one is there from the company to observe the sampling, ensure the persons involved are who they claim to be, and appear in court if necessary to testify. So if it turns out you're NOT the father, you're going to have to have the testing done again by a company that will produce admissible results. Be aware that the time you have within which to contest your child's paternity is usually pretty limited, so you might want to get going on that.
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