Bride uses wedding day to make co-parenting promise

"Co-parenting means sharing the duties of a child."

No one knows this better than two couples whose friendship may have seemed like an unlikely one five years ago.

Katie Musser told the story, in a Facebook post, of the love she shares with her new husband, his child, and the child's mother and stepfather.

"Life is so unpredictable," Katie began.

Katie met her husband, Jeremy on April 17, 2013. After about six weeks of dating, Jeremy revealed he and another woman had a child together - and the baby was born on April 28.

"I sat in my apartment in utter shock," Katie wrote in her post. "A million questions going through my mind. I had known him for 6 weeks? And his son was 3 weeks? Why didn't he tell me? How do I react?"

But instead of walking away, something inside Katie made her say, "That's so exciting!"

Katie and Jeremy continued to date and developed a relationship, but meanwhile, Jeremy was a new father, navigating co-parenting with his son, Landon's mother.

Katie admits, she and Landon's mother, Casey did not get along.

"So many stories, rumors, and judgments, but what would you expect?" Katie reflects. "That's all we ever saw. That's the norm. You don't like the 'other person.'"

Katie said she also struggled with trust from the day Jeremy told her about Landon, asking herself if there were any other hidden secrets. But she says she wanted to trust him and have a healthy relationship with a man for whom she developed a deep love.

Katie decided the best way to move forward was to stop pushing back.

Just before Landon's first birthday, Katie reached out to Casey.

"I spoke nothing but truth to her. It was not easy. You can't trust someone in a second," Katie remembers.

But soon, the two began having mommy dates. They talked about life and relationships - but most of all, Landon.

After all, Landon had known both Casey and Katie his entire life, thus far.

"Landon was and is the beat to our heart. The little guy who not only changed our routines and norms, but he changed us. Giving us patience, understanding, and love," Katie wrote. "I may not have been there for his first step, potty training, or his first dentist appointment, but Casey respected me like I was. She still treated me like his mom."

So their lives rolled on. Casey got married to a man named Tyler, who Katie says was very respectful of the women's friendship. But Jeremy and Tyler were a different story.

Katie, having been in this situation before, hoped Jeremy would learn from her mistakes, and he eventually did. Jeremy reached out to Tyler, the same way Katie had to Casey.

"Jeremy thanked him for raising Landon and being the dad he wasn't. He told him that he wasn't his only daddy, but they both were," Katie said. "After that, things got easier."

And things became clearer for Katie and Jeremy, who decided to become husband and wife.

Katie wanted to profess her love for Jeremy in front of family and friends, but she also wanted to make commitments to Casey and Landon, too.

On her wedding day, Katie and Jeremy stood at the altar, preparing to say their vows, but first Katie turned to Casey, Tyler, and Landon.

"First, I want to thank you for accepting me as your friend and allowing me to be a part of Landon's life," Katie said, standing at the altar with Jeremy.

She went on to promise to be a good co-parent and mother for Landon and to respect the roles they play in the little boy's life.

Katie then called Landon, now 4-years-old, to stand with her and Jeremy at the altar. Katie kneeled down to Landon and told him she loved him more than he would ever know.

"I'm so happy that I now, officially get to be your bonus mom," she said through tears and laughter.

She promised to protect him, love him, and "clean all the boo-boos" he ever gets.

Katie says Jeremy and Tyler also further bonded the night of the wedding, sharing some time to talk alone about the new life ahead of them.

"I know I can speak for us all, parenting is hard yet amazing, but co-parenting? It's a blessing," Katie reflected on her time so far with Jeremy. "It was the hardest and best four years of my life. It takes true understanding and support from the ones who love you."

Katie acknowledged the special relationship this five-person, blended family shares is not for everyone and it definitely comes with its challenges. But she says it's possible to get along, communicate, and give respect to people with whom you share your life.

But Katie's advice is to, "Go against the norm. Be that change."