Songfacts®:

• In 2013, Alex & Sierra won Season 3 of The X Factor. Their prize included a $1 million recording contract from Sony Music Entertainment, which released their debut album, It's About Us, the following year. "Just Kids" is part of that album, which ended up being their last; they broke it off romantically in 2016 and found they couldn't make it work professionally either.
• Alex & Sierra wrote this with Sam Hollander (Neon Trees, Gym Class Heroes), Ali Tamposi (Kelly Clarkson) and John Ryan (One Direction). Sierra recalled to Artist Direct: "We had this writing camp at a friend's house. It was us and ten other singers and songwriters. We had known them for months when we were on The X Factor, and they had seen us go through lots of ups and downs. They were all literally like our family. We were at this writing camp. It was a musical summer camp with friends. We'd go in the Jacuzzi and have fires and snacks. It was like a party, and here and there we'd write songs. Technically, we're not the age of children, but it felt like we were all a bunch of kids hanging out with our friends."
  
  Alex added: "That was just a fun song. It was lighthearted and something we could dance to. The chords aren't very difficult. The lyrics are fun."