<human>: Can you succinctly summarize the text in 1-3 sentences?

This is a throwaway (she knows my account) 

Title says it all. We've been together for 3 years. Engaged for 8 months. We are both graduating with our bachelor's degrees in may, so we have postponed wedding plans until we graduate. 

In August of this year her Aunt's family took a "vacation" from Venezuela to the U.S. She is very close to her cousins. The intentions were for them to come and stay here. Essentially come illegally.

Now, I am very sympathetic to this topic. My parents were illegal immigrants and they are both now citizens. This all occurred in the 80's so I imagine the laws were much different then. 

A few weeks ago, she brought up the topic of her dad's request of giving her cousin who is the same age she is her SS#. I immediately stated that is a terrible and dangerous idea. That this could have the potential of destroying our financial future, and her personal future. She stayed quiet and switched topics. I thought the issue was cleared up. 

Today she tells me that her mom is stopping by to pick up her SS Card! I was floored! I just excused myself and went to my dorm! I feel like she is not considering how this can affect OUR future! I feel bad for her cousins, but this seems wrong. 

I need help knowing how to approach this topic to her and/or her family. Her family absolutely LOVES me. They trust me and they feel like I am great for their daughter. I just feel like no one is seeing the big picture here.

Any advice? Thank you.
<bot>: Advice needed how to approach my fiance and/or family that lending her SS card is a terrible idea and it will affect our future.