KJV: For this cause shall a man leave his father and mother, and cleave to his wife.

NIV: For this reason a man will leave his father and mother and be united to his wife.

ESV: Therefore a man shall leave his father and mother and hold fast to his wife.

CSB: For this reason a man will leave his father and mother.

NASB: For this reason a man shall leave his father and mother*  — with a footnote, “Many late mss add and shall cling to his wife.”

NLT: For this reason a man will leave his father and mother* — with a footnote,  “Many late mss add and will be united with his wife”.”

Internal evidence

The phrase is added based on the original statement in Genesis 2:24 and as quoted in Matthew 19:5 (and Eph 5:31).

UBS gives the omission of the words a C rating.