TLDR: The On My Block cast was significantly older than their characters. Sierra Capri was 19 playing 14, Jason Genao and Brett Gray were both 21 playing 14, and Jessica Marie Garcia was a shocking 30 years old playing a 15-year-old high school freshman. The age gaps allowed the show to tackle heavy topics like gang violence and PTSD with mature actors.
If you watched On My Block and thought the cast looked a little too polished to be actual high school freshmen, your eyes weren’t deceiving you. The Netflix coming-of-age drama pulled off one of the most dramatic examples of the “Dawson’s Creek effect” in recent TV history.
When the show premiered in March 2018, the four main characters were supposed to be 14 years old, navigating their first year of high school in the rough Freeridge neighborhood of Los Angeles. But the actors playing them? They ranged from 19 to 21 years old. And one supporting cast member playing a fellow student was a full 30 years old.
Here’s the breakdown of how old the On My Block cast really was, and why the show needed older actors to tell its story.
Sierra Capri Was 19 Playing 14-Year-Old Monse
Sierra Capri, who played the headstrong Monse Finnie, was born on September 8, 1998 in Baltimore, Maryland. When On My Block premiered in March 2018, she was 19 years old playing a 14-year-old.
That’s a five-year age gap, which actually made her the youngest of the main cast and the closest to her character’s actual age.
What makes Capri’s casting even more interesting is her background. Unlike her co-stars who mostly came up through traditional acting routes, she was a biology major in college before pivoting to acting. That outsider perspective brought something genuine to Monse, who was written as the group’s direct, no-nonsense leader.
The five-year gap was small enough that cameras could linger on her face without breaking the illusion. At 19, the physical differences between late and early adolescence are minimal enough to work on screen, especially with the right styling.
Jason Genao Was 21 Playing 14-Year-Old Ruby
Jason Genao, who played the neurotic math genius Ruby Martinez, was born on July 3, 1996 in Jersey City, New Jersey. He was 21 years old when the show premiered, playing a character who was 14.
That’s a seven-year age gap, and it was intentional. By the time On My Block aired, Genao already had some serious credits. He’d appeared in Netflix’s “The Get Down” and played a young mutant in the critically acclaimed film “Logan” with Hugh Jackman.
The age gap became really important in Season 1’s finale when Ruby gets shot, then spends Season 2 dealing with PTSD. That’s incredibly heavy stuff that needed an actor mature enough to handle it without getting messed up.
Genao researched PTSD extensively and drew on personal tragedy – his own cousin had been shot twice. He had to get inside the head of a 14-year-old who’d never experienced violence before. An actual 14-year-old actor might have really struggled to separate that trauma from real life.
Brett Gray Was Also 21 Playing 14-Year-Old Jamal
Brett Gray, who played the eccentric conspiracy theorist Jamal Turner, was born on August 7, 1996 in Philadelphia, Pennsylvania. Like Genao, he was 21 when the show premiered, also playing a 14-year-old.
Gray wasn’t just an actor. He’s also a singer and musician who released his debut single “Old Thing Back” in June 2018 and an EP called “Easy Daze” on his birthday that year. He’s been compared to Usher for his musical style.
That musical background shows up in his performance. Jamal’s dialogue came out in rapid-fire bursts, and his physical comedy had this dance-like quality to it. Gray’s training as a musician helped him nail the timing and rhythm that made Jamal so funny.
Comedy is also notoriously difficult. Playing “funny” requires confidence and zero inhibition. Being 21 instead of 14 gave Gray the freedom to fully commit to Jamal’s absurd treasure-hunting storylines without the self-consciousness that trips up actual teenagers.
Diego Tinoco Was 20 Playing 14-Year-Old Cesar
Diego Tinoco, who played Cesar Diaz, was born on November 25, 1997 in Anaheim, California. He was 20 years old when the show premiered, playing a 14-year-old character.
Tinoco’s heritage is Mexican and Ecuadorian. His father is from Michoacán, Mexico, and his mother is from Quito, Ecuador. He grew up speaking English and Spanish, identifying as “100% Latino and 100% American.” Being fluent in both languages and cultures was huge for playing Cesar, who’s embedded in the Santos gang world.
At 20, Tinoco had the physical maturity that distinguished him from his co-stars. While all four were playing 14, Cesar was written as the “tough” one who’d been initiated into gang life. The show needed him to look like he could survive in prison or a street fight, even if his spirit was gentle.
The romantic subplot with Monse also benefited from the actors’ real ages. With Tinoco at 20 and Capri at 19, their intimate scenes could be filmed ethically and comfortably without any awkwardness.
Jessica Marie Garcia Was 30 Playing 15-Year-Old Jasmine
Here’s where things get really wild. Jessica Marie Garcia, who played the loud and lovable Jasmine Flores, was born on March 23, 1987 in Orlando, Florida. When the show premiered in March 2018, she was 30 years old.
She was playing a 14 to 15-year-old high school student. That’s a 16-year age gap, double the age of her character.
Garcia wasn’t a newcomer trying to pass as young. She was a Disney Channel veteran with credits including “Liv and Maddie” and roles in “The Middle.” Her years in the Disney ecosystem taught her how to play broad comedy without losing the human element.
Jasmine was a high-energy character who was loud, confident, and lacked social filters. Playing someone like that takes seriously good comedic timing that comes from years of experience. Garcia’s maturity let her dominate scenes with larger-than-life energy that felt intentionally over-the-top rather than trying too hard.
In comedy, audiences often give a pass on age realism because the performance is exaggerated. As the series progressed, the writers used Garcia’s actual emotional depth to turn Jasmine from a caricature into a role model for self-love, a transition Garcia navigated with the wisdom of someone in her 30s.
Julio Macias Was 28 Playing Cesar’s Older Brother Spooky
Julio Macias, who played Oscar “Spooky” Diaz, was born on March 20, 1990 in Mexico City, Mexico. He moved to the United States as a child.
When the show premiered in March 2018, Macias was exactly 28 years old playing a character in his early 20s. While this was more age-appropriate casting, the gap between him and Diego Tinoco (who played his younger brother) was crucial.
Macias at 28 needed to look way older than Tinoco at 20 to sell the whole big brother dynamic. Spooky was supposed to be the authority figure, the gang leader raising his younger brother. If they’d cast a 22-year-old, that authority wouldn’t have landed the same way.
Macias’s success on On My Block propelled him to other major roles, including playing Pete Astudillo in “Selena: The Series.”
Why the Show Needed Older Actors
On My Block wasn’t a lighthearted teen sitcom. It was a dramedy that tackled gang violence, deportation, homelessness, and PTSD. The show had a high body count and didn’t shy away from dark themes.
Using grown-up actors gave the show some breathing room ethically. Showrunners could tackle really dark stuff (Cesar getting “jumped in,” Ruby’s shooting and PTSD) because the actors were adults who could leave the heavy emotions on set when filming wrapped.
There were practical reasons too. Child labor laws limit how many hours minors can work on set. Adult actors could work longer days, making complex shooting schedules actually possible. Plus, they brought years of professional experience that made the performances deeper and more believable.
The physical demands were real too. The actors have discussed the intense conditions of filming, and asking actual 14-year-olds to handle those schedules while also processing traumatic storylines would have been problematic.
The Season 4 Time Jump Closed the Gap
By Season 4 in 2021, the cast’s real ages had caught up with them in a way that was becoming hard to ignore. Sierra Capri was 23, Jason Genao was 25, Brett Gray was 25, and Diego Tinoco was 23.
At 25, Genao and Gray were fully grown men. Continuing to write them as 15 or 16-year-olds would have strained believability to the breaking point.
The show did a two-year time jump, aging the characters to around 18. This let the actors tackle storylines about college, careers, and adult relationships that made way more sense for where they actually were in life. It was a smart move that worked with the cast’s real ages instead of fighting against them.
The age gaps in On My Block weren’t a mistake. They were totally intentional, letting the show tackle darker and more complicated stories than would’ve been possible with actual teenagers.
The result was a critically acclaimed series that felt real while also dealing with the practical realities of making TV.
