No. At 18 an individual is technically no longer considered a child but an adult. If an individual is old enough to go to college then that person is an adult whether they act like it or not. An 18 year old from another country shouldn’t be up for adoption. That person may qualify for a work or school visa, but otherwise if they want to remain in this country they must acquire a green card or go through the process of becoming a citizen. Even with work and school visas it is imperative that there is a thorough background check. Even so, individuals with visas and green cards have not earned the right to vote!