Jason and Tiffany Mertlich decided to participate in a growing trend and have a "gender reveal" party for their fourth child.
Recently, many parents have learned the gender of their baby by doing something such as opening a box of either pink or blue balloons, hitting a piñata that releases pink or blue confetti, or cutting into a cake with the color pink or blue inside.
But instead of asking friends and family to help surprise them in one of these ways, the Mertlichs planned a reveal party for their three children.
Gunner, Paisley and Harper are all shown in the family's YouTube video, gathered around the table as they prepare to find out the gender of their new sibling-to-be. They are asked what they believe the gender will be: Gunner guesses a boy, Paisley a girl and Harper simply guesses it will be a baby.
A cake is then set in front of them. Gunner cuts it open and, to his dismay, finds a pink slice of cake inside. Gunner reacts with obvious disappointment, questioning if it really is true. Once his dad confirms that he will indeed have a little sister, the tears begin to flow.
"It's OK, Gun. It's all right," Jason Mertlich says in the video.
But as Gunner continues to cry, Jason Mertlich admits that he had a similar reaction when he found out. Gunner continues to cry as he refuses to eat the "girl" cake.
"It has jelly in it," his sister pipes in. But nothing seems to help.
"I knew it was a girl," Gunner cries. "I hate girls. Every time it's girl, girl, girl, girl. It's always going to be girls. ... It's too much."
The video continues on as Mertlich tries to console his son. Since the video was posted to YouTube video six days ago, it has received almost 100,000 views.
Earlier this week, the Mertlich family also did an interview with Right This Minute regarding the popular video. When asked how he's doing now, Gunner admits that he's going to be OK.
"I told him that now he gets to spend all the dad and son time with me and doesn't have to share with anybody," Jason Mertlich said.
But when asked how he's going to explain to his daughter why he wasn't as happy with finding out it was a girl, Jason Mertlich admitted that he should have kept quiet.
"Well, sometimes I guess we should have bit our tongue," Mertlich said on Right This Minute.
Many viewers have commented about the statement and their concern for the new child, but the Mertlich family explained they just needed time to adjust to the news.
Online commenters also sympathized with the Mertlichs, having experienced the same situation in their own families.
"Aww Gunner! I felt the same way when I found out that my mom was having a boy after having twin boys," Jasmin Ann wrote online.
"You'll be thankful when you're older. Being the only boy/girl among your siblings is a blessing. You don't have to share clothes, toys and you get spoiled most of the time. Cheer up, Gunner!"
Others pointed out how Gunner may change his feelings about having sisters in the future.
"He says this now but as the older brother no one is going to be more protective of his younger sister than he is. The irony!" Peter Kim wrote.
The Mertlich family is not alone when it comes to kids having an emotional reaction to the gender of their new sibling. Lance Andrews posted a video last year of his daughters Maisy and Finley finding out they were going to have a little brother.
Although Finley was not initially excited for a brother, Andrews posted an update noting that things have worked out just fine. "Finley quickly got over her initial reaction and loves her little brother."
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