Transcript for Mom who started gender reveal trend has reservations on how the events have evolved
Reporter: We've seen the videos parents-to-be excitedly cutting into a cake or opening a box of balloons. Their loved ones gathered in anticipation. Then the big moment. Gender reveals have become a modern tradition almost as common as baby showers. With expecting parents pulling out all the stops. Who run the world who run the world girls Reporter: Others ending in near disaster. Video tonight a father revealing the gender of their baby ignited a massive wildfire. We did the whole thing. Reporter: But now the woman who helped start this viral trend is questioning what that first glimpse of pink or blue represents. You know, it's been an evolution of thought, you know. And nobody was thinking about gender like we do now in 2008. I wasn't thinking about it. I thought there's pink or there's blue. Reporter: In 2008 when Jenna carvanitasing learned she was pregnant with her first child she couldn't wait to surprise her family with the sex of the aby. We had a little difficulty getting our family started. So when we got pregnant with Bianca we were overjoyed. I wanted to draw nefrn in the family pi wanted everyone to match my excitement level. Did you want a boy or a girl? Did gender matter to you? You know, it really didn't. We were just celebrating a milestone in our pregnancy. Reporter: She threw a party where she cut into a pink cake announcing a girl then post bd it on her blog, never expecting it to take off. You invented the gender reveal party. People have been celebrating Herr baby's biological sex since ultrasounds were invented. I was just that person who elevate TD on social media. Reporter: Ten years later she's rethinking the concept. Problem is the expectations we're putting on our kids. Some of those kids may 100% gravitate toward whatever you've put in their gender reveal cake. But some of them won't. Reporter: Her daughter Bianca celebrated at that party now hoping to inspire this new perspective. Plot twist. The gender reveal baby actually wears blue suits when she wants to get dressed up. Reporter: Jenna posting this photo and writing on Facebook "Assigning focus on gender at birth leaves out so much of their potential and talents that have nothing to do with what's between their legs." She's just never been into she's never gone that direction really. And she picks out her own clothes and she wears what she wears. Have you talked to Bianca about gender and how she identifies? Yeah. She has those conversations with me. She's really leading the way. She's like mom, there's more than two genders. There's a couple. There's many. She's not telling me she's a certain gender. But she identifies as a girl. But the point is being a girl doesn't mean you have to be in this one box. Absolutely. If they're telling young? About themselves or the way they see the world, it's just important to listen and not be judgmental about it. Reporter: Since Jenna cut the cake in 2008 the popularity of gender reveals has exploded. In addition to sharing this news with you are why friends and family there's an element of exhibition. You want to show off. You're proud. You're excited. Reporter: There are now thousands of gender reveal videos on YouTube, some racking up millions of views. They capture moments of pure joy like this mother of six boys seeing that pink icing for baby number 7. And sometimes disappointment from older brothers and sisters occasionally even from mom and dad. Boston Celtics player Gordon Hayward with this genuine reaction learning his family was welcoming a third girl. Is daddy happy? Daddy's always happy. Reporter: All of this starting off a childhood hued by blue and pink marketed to parents. It does play into this idea that compels parents to buy the certain color if they know they're having a boy or girl. But girls aren't giving this message if it isn't pink it's not for me. So it's kind of like I started to realize I need to do more of my part to get it out there that we're not just pink. Reporter: As Jenna has learned, not all kids can be put in one gender box. Jean Malpass is an expert on gender identity. A boy, a girl, both, neither. And everyone has a gender identity. And everyone come to understand their own gender identity at their own time. Reporter: He believes society shouldn't reinforce gender stereotypes with reveal parties. What we know is that gender stereotypes are actually often they reduce, they simplify the complexity that we all have as humans. Reporter: Others look at it differently. I don't think parents should worry at this stage when they're celebrating their baby's gender. Whether or not that child's going to grow up to become transgender. Reporter: Nicole Russell is a mom of four who wrote an article in 2017 titled "Relax, parents, it's okay to have gender reveal There are milestones to every child. And the first one that you -- that you reach was often the baby's gender. I think picking on people who celebrate the gender of their babies even if it is very extravagant seems petty. Reporter: She believes parents should celebrate within reason. I'm just not in favor of a gender party that would burn down a house or endanger the poor child in utero. It's just cut cake. After that first baby girl Jenna went on to have two more daughters, three girls, three very different personalities. You think these parties are going to continue? I think they're going to continue. My hope is they're having some conversation a little open-minded about what gender really means and what that really means for everyone in our community and also our children, however they may decide to live their lives. Reporter: For "Nightline" I'm Marcy Gonzalez in Los Angeles.
This transcript has been automatically generated and may not be 100% accurate.