Role in the series
Carmen and Julio make their debut in "A Day to Remember".
Since childhood, Carmen and Julio were very close and whenever they had an argument their grandmother always knew how to cheer them up. After Doña passed away, Carmen was determined to follow in her grandmother's footsteps, but her cooking was terrible and the restaurant was close to being out of business. Julio was willing to sell the restaurant, but Carmen refused to give it up.
On the Day of the Dead, Carmen and Julio were visited by Princess Elena, who, after discovering that she could see spirits, had come to help them save the restaurant on their grandmother's request. When they find Angelica's cookbook, Carmen decides to save the restaurant with the recipes in it, but Julio simply decides to sell the cookbook too. This causes the two to have a row that gets the cookbook destroyed. Elena, with help from Dona Angelica's ghost, tells Carmen her grandmother's recipes and makes paella with one which she feeds to Julio. This makes the two reconcile and decide not to sell the restaurant.
The pair's next major role is in "Navidad". They first appear at Avalor Palace with Dona Paloma to invite Elena to their Navidad celebration on Nochesbuena. To convince her to come, Julio tells Elena how they celebrate Navidad. Elena tells everyone that they will all celebrate in Castillo Park. Julio is amazed when Naomi and Daniel Turner bring a boat. When everyone starts fighting, Elena proposes a Navidad Parade. Dona Paloma tells him that Elena will pick the float belonging to the people she believes celebrate Navidad best to lead the parade. Hearing this makes Carmen and Julio buy as much as they can from her store. However, everyone's attempts to outdo each other causes a fight that ruins everything and makes everyone decide to just go home. On the way, Carmen and Julio run into a parrenda led by Elena which they join in. They apologize to the others on the way to Avalor Castle and celebrate together.