Teen Mom is filled to the brim with sadness, right?
All kinds of sadness too - we've seen children neglected, we've seen parents deal with drug addiction and domestic violence and prison.
But there's nothing quite like this.
There's one story that pretty much takes the sadness cake when it comes to this show, and that's the story of Leah Messer's daughter, Ali.
Ali is one of the twin girls that the West Virginia native gave birth to as a teenager, and she suffers from a rare form of muscular dystrophy.
If you watch Teen Mom 2, you're familiar with this.
On the show, we've seen Leah and Ali's father, Corey Simms, struggle for years to figure out exactly what was wrong with Ali.
That process has been as emotionally exhausting for the parents as it has been medically challenging for the little girl herself.
We've all seen saw how stressful, tiring and heartbreaking it's been - especially as they realized how serious her condition is.
We've seen them be told time and time again that she needs to use her wheelchair and to wear a helmet and to get help.
We've seen them slacking on that, however sweet their intensions are, so that she could have a more "normal" childhood.
Their efforts may be largely in vain. It's the nature of Ali's condition that as time goes on, the disease will get worse and worse.
We can't even imagine how difficult all of this must be.
Imagine having to watch this from Leah's perspective. It must consume her life, day in and day out, and in every respect.
It's an ongoing struggle, and thanks to this ridiculously tragic story she shared on Twitter, we can get a little glimpse of it.
"As I'm doing Ali girls makeup she looks at me and says 'Mom, what's it like to see with two eyes?' ..." she wrote.
"Everyday I wish I could take her place but I know there's a greater purpose!" she added. "Just broke my heart."
Way back when Ali and Gracie were toddlers, Leah began noticing that there was something wrong with Ali's eyes and legs.
Those were the first signs of her disease.
Since then, the precious little girl has been wearing glasses, and now it's clear that she's not even able to see out of one eye.
As Leah explained after this initial tweets:
"This is the first time she's asked" anything about her eyes, and "she's starting to ask a lot of questions like this."
Thankfully though, Leah seems to have a good attitude.
Someone told her that Ali loves her life and she wouldn't even want to switch places. Which, yeah, obviously, it's not like Leah was proposing a Freaky Friday scheme.
"Ohh for sure!!" she replied. "I don't think of it negatively at all. It's just like, dayyyyuum. Sooo many take the little things in life for granted."
She also retweeted a bunch of nice messages about Ali.
Encouraging things fans wrote to her like "You continue to do everything you can for her and your love for her shines."
"Some days are tough," another supporter of the realitty starwrote, "but always focus on her smile and cherish every memory."
And also "She will be phenomenal because of her struggles. She will not struggle in vain. She has purpose. Purpose to overcome."
"She will live a beautiful life."
Thanks to her fans for lifting her up, because she really can use it amid such hardship, and thanks for the good, hard cry, Leah!