The NRA's press release after the amendment's defeat explicitly referenced this lie:
This amendment would have criminalized certain private transfers of firearms between honest citizens, requiring lifelong friends, neighbors and some family members to get federal government permission to exercise a fundamental right or face prosecution.
In fact, the amendment's actual language protected private transfers (ie, transfers that are not preceded by advertising in venues like publications or the Internet). Let's look at what the language actually said. The following is a specific exemption for transfers to family members:
the transfer is made between spouses, between parents or spouses of parents and their children or spouses of their children, between siblings or spouses of siblings, or between grandparents or spouses of grandparents and their grandchildren or spouses of their grandchildren, or between aunts or uncles or their spouses and their nieces or nephews or their spouses, or between first cousins, if the transferor does not know or have reasonable cause to believe that the transferee is prohibited from receiving or possessing a firearm under Federal, State, or local law
So you'd have to be speaking about someone who is at least a second cousin before this exemption did not apply. Is the NRA really going to the mat to protect gun transfers between second cousins?
How about transfers to friends or neighbors? Politifact rated that claim "mostly false." Their opinion states:
The amendment specifically exempted family and friend transfers from the requirement to conduct a criminal background check. But it did extend the requirement to Internet and gun show sales. So only if a friend or family member purchased a gun in one of those settings would the background check requirement kick in. That’s a limited circumstance, to be sure.