'Son in law' in the Bible

And David said to Saul, Who am I? and what is my life, or my father's family in Israel, that I should be son-in-law to the king?

And Saul said, I will give her to him, that she may be a snare to him, and that the hand of the Philistines may be against him. Wherefore Saul said to David, Thou shalt this day be my son-in-law, in the one of the two.

And Saul commanded his servants, saying, Commune with David secretly, and say, Behold, the king hath delight in thee, and all his servants love thee: now therefore be the king's son-in-law.

And Saul's servants spoke those words in the ears of David. And David said, Seemeth it to you a light thing to be a king's son-in-law, seeing that I am a poor man, and lightly esteemed?

And when his servants told David these words, it pleased David well to be the king's son-in-law: and the days had not expired.

Wherefore David arose and went, he and his men, and slew of the Philistines two hundred men; and David brought their foreskins, and they gave them in full number to the king, that he might be the king's son-in-law. And Saul gave him Michal his daughter for a wife.

Then Ahimelech answered the king, and said, And who is so faithful among all thy servants as David, who is the king's son-in-law, and goeth at thy bidding, and is honorable in thy house?