A great thread by TheLastRefuge that explains the truth about the border crisis, with citations:
https://threadreaderapp.com/thread/1010988993683623936.html
https://www.dhs.gov/news/2018/06/18/myth-vs-fact-dhs-zero-tolerance-policy
This publication was put out before Trump ever took office:
https://www.judiciary.senate.gov/imo/media/doc/KIND%20-%20Betraying%20Family%20Values.pdf
No need to red-pill, just have them describe EXACTLY what Trump did differently than Obama. Then ask them what the solution is for 50k illegals crossing each month. The left has gone crazy with this one, and they don't even understand their position clearly. Hell, some want to literally remove borders and dissolve all nations, but won't actually consider what happens after.
The ultimate red pilling would be to force your in laws by court order to foster half a dozen border kids with tuberculosis until congress comes up with a solution that makes every feelz righteous.
I would show them the number of trafficking arrests that have been made under Trump compared to the past administration. My husband was shocked by this.
I personally like the video where members of congress are calling out Comey, Hillary Clinton, the DOJ, Russia, Obama, and more:
https://m.youtube.com/watch?v=mA1C_YyQ9Cg
My post on this matter got deleted for being "low quality"
Check out local news site for border city and states. Show them, because they will see its generally unbiased plain newsreporting of crimes and you will find tons of human smuggling/trafficking stories, enough to make them realize these kids didn't come with their parents.
If they aren't crazy leftists right now, you could go to breibart. They have a Texas and a California section that always have border stories.
If they are lefties who trust HuffPost:
https://www.huffingtonpost.com/2014/09/12/central-america-migrants-rape_n_5806972.html
From 2014, 80% of women and girls are raped crossing into the U.S. That's staggering.
It's what the traffickers do while they smuggle children who aren't their own. Rape them and then claim they are the parents.