President Trump's 18-year-old youngest son, Barron, was in the spotlight during his father's inauguration on Monday.

Standing 6 feet 9 inches tall, many attendees and spectators commented on how mature the young Trump has become since his father first took office in January 2017.

At 10 years old, Barron Trump was often the victim of cruel jokes and rumors from his father's critics. His mother, Melania Trump, has tried to protect him from unwanted scrutiny, sometimes to no avail.

The eldest son earned the respect of onlookers as he stood beside his father at the inauguration ceremony on Monday. Here's how Barron Trump has grown since 2017.

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2017

At age 10, Barron Trump became the first son to win the White House since John F. Kennedy Jr. in 1961.

Barron, who turned 11 in March 2017, also lives in Trump Tower, New York, and attends Columbia Grammar Preparatory School on the Upper West Side.

Rumors began to circulate in 2016 that Barron Trump might be autistic, amplified by comedian Rosie O'Donnell. In 2024, Melania Trump said the rumors had a profound impact on her son, who was bullied at school.

'I am appalled by this cruelty' Melania Trump she wrote in her memoir. "It was clear to me that she was not interested in raising awareness about autism. I felt like she was attacking my son because she didn't like my husband."

"There is nothing shameful about autism (despite O'Donnell's tweets alluding to autism), but Barron is not autistic," she added. “Barron’s experience of bullying both online and in real life following the incident clearly demonstrates the irreparable damage done.”

2018

Barron turned 12 in March 2018, and he remains a common target of Trump’s enemies.

Actor Peter Fonda called on officials to "take Barron Trump from his mother's arms and put him in a cage with pedophiles." He later apologized for the remarks.

"I tweeted some highly inappropriate and vulgar content about the President and his family in response to the devastating images I saw on television," Fonda said in a statement shortly afterward. "Like many Americans As a person, I am passionate and distraught about children being separated from their families at the border, but I have gone too far."

2019

Barron was 13 when his family moved permanently to Mar-a-Lago in 2019. That year, Trump said it would be "difficult" for him to allow his son to play football.

“I just don’t like the coverage that I’m seeing as it relates to football — I mean, it’s a dangerous sport and I think it’s really tough,” Trump said at the time. "I thought the equipment would get better, and it has. Helmets have gotten better, but it doesn't solve the problem."

During a 2019 House Judiciary Committee impeachment hearing, Stanford University law professor Pamela Callan said then-President Trump could "name his son Barron, but he couldn't make him a baron."

Melania Trump was upset that her young son was mentioned during the hearing.

"Minor children deserve privacy and should stay out of politics," the first lady tweeted at the time. "Pamela Callan, you should be ashamed of yourself for your outrageous and clearly biased behavior of public pandering and for using a child to do it."

2020

As Trump fights for re-election in 2020 and the COVID-19 pandemic rocks the country, Barron Trump continues to attend school and stay out of the public spotlight. In 2020, Jeopardy host Ken Jennings apologized for a joke he told about Barron in 2017.

"Barron saw a very long tie and a bunch of expired deli meat in the dumpster," Jennings tweeted at the time. "He thought it was his dad and his heart was broken."

“Hey, I just want to acknowledge the fact that I’ve definitely posted some unartistic (sic) and insensitive things on Twitter over the years,” Jennings wrote in 2020. “Sometimes they’re in my It's a joke in my head and I'm frustrated by the way they read it on the screen."

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2021

Barron Trump's father was 14 when he left office in January. He and his mother live full-time at Mar-a-Lago, away from the spotlight.

In July 2021, he was seen leaving Trump Tower with Melania Trump.

2022

Barron Trump was 16 when FBI agents raided his father's Florida estate. He has kept a low profile this year, but was seen in public with his parents at the funeral of Trump's first wife, Ivana Trump, in July 2022.

In November 2022, his father announced his candidacy for president.

2023

When President Trump's campaign launches again in 2023, Barron remains absent from the public spotlight. In August of the same year, photos of his father were released.

2024

Barron Trump will enroll at New York University (NYU) in the fall of 2024. In May, he graduated from Oxbridge College in West Palm Beach and was seen taking classes at New York University's Stern School of Business.

In November, he also voted for the first time, voting for his father in Florida.

2025

Barron looked sharp as he attended his father's inauguration on January 20. Later in the day, he waved to the crowd after his father mentioned his role in the 2024 campaign.

"I have a very tall son named Barron. Has anyone heard of him?" Trump's eldest son waved to the attendees, and cheers broke out.

"He understands the youth vote. You know, we won the youth vote by 36 points ... and he said, 'Dad, you gotta get out, Joe Rogan, all these people get out,'" Trump recalled. "We did it, we did it. Joe Rogan was great."

The 18-year-old also wowed attendees when he shook hands with President Biden and then-Vice President Kamala Harris, leading some social media users to speculate on a possible future political career.

“Barron Trump just shook hands with Joe Biden and Kamala Harris,” one X user wrote. "This kid is going to be our president one day. Make your bets."

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“Barron Trump is a natural,” another said of Barron. "Completely own this moment."

Fox News Digital's Brooke Kotto and Kyle Schmidbauer contributed to this report.