近亲繁殖

inbreeding

near / close to / approximately

close relative / near relation

parent / one's own (flesh and blood) / relative / related / marriage / bride / close / intimate / in person / first-hand / in favor of / pro- / to kiss / (Internet slang) dear

parents-in-law of one's offspring

old variant of 繁[fan2]

complicated / many / in great numbers / abbr. for 繁體|繁体[fan2 ti3], traditional form of Chinese characters

to breed / to reproduce / to propagate

to grow / to reproduce