近親交配

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

to hand over / to deliver / to pay (money) / to turn over / to make friends / to intersect (lines) / variant of 跤[jiao1]

mating / copulation (esp. of animals)

to join / to fit / to mate / to mix / to match / to deserve / to make up (a prescription) / to allocate