These days, Kailyn Lowry and Jenelle Evans are the most bitter of enemies.
In fact, it often seems that the Teen Mom 2 co-stars can't go a day without throwing jabs at one another on Twitter.
But believe it or not, it wasn't always like this.
In fact, there was a time when Kail and Jenelle were not only friends, but kindred spirits.
Dive into the gallery below for a full run-down of how these two went from besties to rivals:
1. Better Days
In the months after they both found stardom on MTV, Kail and Jenelle became close friends and bonded over their difficult circumstances.
2. Kindred Spirits
In the early days of the 16 and Pregnant/Teen Mom franchise, Kail and Jenelle were among the most "at-risk" participants.
3. Always the Rebel
Jenelle's penchant for bad behavior became apparent very early on -- and her brushes with the law began before she was old enough to vote.
4. Troubles of Her Own
Like Jenelle, Kail clashed with her family beginning at a young age, but unlike Jenelle, she was in no way to blame for the situation.
5. Hard Times
Kail received little support from her alcoholic mother or other family members, and she came close to homelessness more than once, often relying on the family of boyfriend Jo Rivera for support.
6. A Bonding Experience
It was around that time that Jenelle asked Kailyn for a favor that would strengthen the bonds of their friendship ...