what maureen mccormack is revealing to "e.t."bout the lowest point of her addiction. >>> first, aaron carter's drug test results. >> cocaine was negative. meth was negative. >> reporter: aaron went on "the doctors" after telling us he wanted to combat what he calls false rumors that he's a drug addict. >> strap me up. ask me if i've smoked meth, crack. >> reporter: the 29-year-old admits to taking prescription drugs. sometimes without a doctor's consent. >> i find myself getting them off the the street. >> aaron is being prescribed medications that caused his sister's death. i don't know that aaron quite grasps that the same thing could happen to him. >> reporter: in a two-part interview, aaron tells travis stork about the loss of his sister and father, enduring body-shaming and reveals, at 5'11", he's only 115 pounds. >> of every test you had done, what was the most you were afraid of? >> hiv. because i'm so skinny. >> reporter: tomorrow on the show, aaron gets his hiv test >> reporter: tomorrow on the show, aaron gets his hiv t