Samuel "Sammy" Valdez, Sr. was @Leo Valdez's great-grandfather and childhood crush of @Hazel Levesque. He went to the St. Agnes Academy for Colored Children and Indians in New Orleans, Louisiana during his childhood before moving to Houston, Texas and starting a family.

History

Sammy Valdez lived in New Orleans during the same time as Hazel Levesque in the 1940s. As a result of Hazel's mother using cursed stones, kids and adults would tease her. Sammy was Hazel's only friend during this time and took care of her. He also took care of the horses owned by rich families and would, occasionally, sneak Hazel into the stables to help him and let her ride the horses. For her birthday, he took her horseback riding and they set up a picnic where he gave her a cupcake. Unfortunately, Sammy would never see Hazel again as Hazel's mother was persuaded to move to Alaska by @Gaea.

After she left, Sammy sold a diamond that Hazel had allowed him to keep, despite promising not to. Using the money, he moved to Houston, Texas like he had always dreamed of. Once there, he opened a machine shop and started a family. Before he died, he got to meet his great-grandson, Leo Valdez and gave him his blessing and asking him to help Hazel if he could.

Legacy

When Hazel made it back to her old home in Alaska, she found an old photo of Sammy, and @Percy Jackson thought he had seen him somewhere before. Later, Percy falls into a pit of muskeg and Hazel jumps in after him, but Gaea forces an image into her mind of an ideal future, including a future version of herself getting married - possibly to Sammy. Hazel says that these visions aren't real and with @Frank Zhang's help, they pull Percy from under the ground. When Leo Valdez sends a video message to @Camp Jupiter, Hazel mistakes him for Sammy, as the two look almost identical, and Percy remembers how Leo looked a lot like Sammy from the photograph, but tells Hazel that it can't be him, as he would be over 70. According to Gaea, he moved to Texas and married at some point, but later died of a heart attack in the 1960s, having never forgotten about Hazel.

As Leo's Spirit Guide

During their trip to Rome, Hazel tries to show Leo who Sammy was by triggering a flashback and pulling him into it. Now seeing Hazel's memories, Leo watched as a large kid named Rufus picked on her, stepping on her lunch, and demanding a diamond for himself. When a diamond involuntarily popped up from the ground, Sammy appeared on the scene holding a dunce cap and using it as a megaphone. He put on a whole show, pretending to be a director while he addressed Rufus and Hazel as movie actors Gary Cooper (originally Clark Gable) and Hedy Lamarr respectively, which Leo incidentally also did when he was younger to deal with bullies. While the growing crowd of people all laughed at Sammy's antics, Rufus only became confused and angry at everyone laughing at him. During the performance, he picked up the diamond and watched as Rufus was carried away inside by kindergarteners when the bell rang a moment later.

After everything calmed down, Sammy picked up Hazel's lunch bag and presented it to her as if it were a crown. Hazel and Sammy joked around, with Hazel worried that Rufus will kill him, but Sammy simply brushed it off and made Hazel laugh some more. When Hazel warned him that the diamond is cursed if he sells it, Sammy promised not to and would keep it as a token of her favor, which she corrects him on. As they headed back to English class, Sammy promised to always be there for her. As Leo watched Sammy, he couldn't help feel that he was simply a eidolon all his life and that Sammy was the real version. He saw Sammy as a confident, smarter, cooler, and funnier version of himself. This slightly depresses Leo, who finally understands why Hazel loved Sammy so much and that he isn't Sammy.

Just then, the flashback shifted again to an old house in a weedy field with an old man sitting on the porch. Leo quickly figures out that Hazel was showing a memory of his life, not hers. The old man calls out to Hazel and the two think he knows they are there, but find out that he was only talking to himself. As the old man thought about Hazel, he used Morse code by tapping his fingers to say I love you. Just then, Leo's mother walked out from inside the house carrying a baby Leo in her arms and introduced him to his great-grandfather. The old man smiled at the baby as he held him and Leo found out that Hazel's power had found the one moment when their two timelines met, as the old man was Sammy.

Sammy held the baby and told him that he hoped to live long enough to meet Hazel one more time, but the curse wouldn't allow him. Leo would have to be his stunt double and tell Hazel something for him. Hazel remembered what Gaea had said about Sammy dying of a heart attack in the 1960s, but that can't be as he is much older. Sammy continued to talk to Leo, telling him that a woman named Doña Callida said that Hazel's great danger would not happen in his lifetime. Because of that, Leo would have to tell Hazel that he was sorry and to help her if he could. He then admitted that he did sell the diamond after Hazel was taken to Alaska, using the money to move to Texas and open a machine stop. However, because he sold the diamond, he had always felt cursed as he never saw Hazel again.

Hazel called out to him, saying that she wanted to come back, but she died. Sammy then gave Leo his blessing and told him to say hello to Hazel for him. He then gave Leo back to Esperanza before saying that he was tired and needed to rest, also saying that he had a good life.