4-year-old's back to school picture shows the value of co-parenting

— -- When an Oklahoma mother posted a photo online of herself with her daughter and her ex-husband's new girlfriend, she didn't expect it to go viral.

But that's what happened when Haley Booth shared a photo of her walking her 4-year-old daughter Rachel to school with Dakota Pitman, the girlfriend of her ex, Caleb Quattrone's.

Booth, 26, and 27-year-old Quattrone, who has been dating Pitman for four years now, were married for four years before divorcing in 2015.

In her lengthy Facebook post that's now garnered more than 14,000 likes, Booth wrote in part: "Don't tell me that peaceful co-parenting isn't possible, because it is. I know it is. Because I do it everyday."

Booth told ABC News she penned the post on Aug. 16, her daughter's first day of school, to show appreciation for her relationship with Pitman.

"I wanted to celebrate the friendship that I have with Dakota. I wanted to show the world that it's possible and that you can achieve something like this," she added, noting that it took "about a year" before the two could peacefully co-parent.

The mother said it helped that it appears her ex-husband is now in a healthy relationship with Pitman. Booth has been in a relationship for three years with her boyfriend, Bryan, who asked ABC News not to use his last name.

"It’s hard… at first, but you get there and once you get there, it’s the best feeling in the world," Booth said of co-parenting.

Pitman was moved when she saw the post.

"I cried," she told ABC News. "They were happy tears. We've come a long way… but I do love Rachel as my own, and it's so wonderful for Haley to accept and love me."

Pitman, who lives 20 minutes away from Booth in Edmond, Oklahoma, notes that the two have a relationship beyond raising Booth's daughter.

"She cuts my hair sometimes. We'll laugh and joke about Caleb. We all get along," she added.

Quattrone added that he's happy the two are agreeable, for the sake of raising his daughter.

"I love it, because it’s good for my daughter and whatever makes her happy truthfully makes me happy," he told ABC News. "Because there’s no other thing that matters except for her."