Definition of adopt:
(v) :
to take by choice into relationship, as, child, heir, friend, citizen, etc.; esp. to take voluntarily (a child of other parents) to be in the place of, or as, one's own child; to take or receive as one's own what is not so naturally; to select and take or approve; as, to adopt the view or policy of another; these resolutions were adopted
"a friend of mine recently adopted a Chinese baby girl found on the streets of Beijing."