. >> reporter: at his office outside los angeles, we asked nikalosi if he remembered treating brian kendallut 14 years earlier. >> i'm not flr wiamiliar with t name at all. >> there have been checks written to the office. but no record? >> no. >> he said your therapy was quite harmful. you told him to butch up, quote/unquote. >> never. that's not our language. >> when somebody says people like yourself -- >> that's a terrible way of phrasing it. i would rather say we're trying to bring out the heterosexuality in you. >> reporter: nicolosi has kept hundreds of children from growing up. a researcher and big believer that homosexuality can be prevented. he worked at a doctoral student at ucla in the 1970s in a government experimental program. he treated a boy named kirk murphy. to turn around kirk's so-called sissy behavior kirk was repeatedly asked to choose between masculine toys like plastic guns and knives or feminine ones. if he chose the feminine items, kirk's mother would be told to ignore him. kirk'ss siblings told anderson his personality changed. >> he had no idea how to relate to pe