Alex Ratnasothy announced to his family twenty years ago that he was embarking on his "greatest adventure yet" in Nepal. He disappeared without a trace.
In April 2003, the 23-year-old's return to Grays, Essex, was scheduled.
He sent an email on February 21st, 2003, letting people know he wouldn't be in touch while on his nearly month-long trek to Everest basecamp.
He told his family in his last moments, "I'll be back before you know it. ".
However, he never did.
When Alex turned 24 years old in July 2003, his sibling Dr. Anna Crozier and his older brother Dr. Joel Ratnasothy took time off of work to visit Nepal. They found that he had been stripped of all of his belongings, including his shoes, and then vanished mysteriously.
Two decades later, according to Dr. Crozier, her father's health is deteriorating and finding answers "suddenly feels urgent.".

Dr. Crozier would have responded that she believed her brother was dead if you had questioned her about his disappearance a week prior.
But as the 20th anniversary of his disappearance drew near, she discovered that she was reviewing the notes she had taken during the 10 months that she had spent looking for him in Nepal.
Now, she speculates that he might have chosen to go undiscovered.
The Chelmsford doctor says, "I thought he can't be alive or he would have contacted us. But now that I think back, I think he was scared after the robbery.".
She says one witness reported seeing a man they thought to be Alex barricade himself into a room at a hostel, demonstrating that he was "clearly distressed.".
Alex would turn 44 at this time. On birthdays, anniversaries, and other family celebrations over the years, he has never failed to be on the minds of family and friends.
According to Dr. Crozier, "it feels like a branch of our tree is missing.".
The day that we all met, which was his 40th birthday, was extremely painful. He wasn't there, so that was terrible. ".

Dr. Joel Ratnasothy, now 46, and Dr. Crozier, now 47, used a local guide to retrace their brother's steps in 2003, a time before social media appeals.
They discovered over the course of a few weeks that he had been robbed of his cash and belongings but had left his passport at a travel agency after attempting to book a flight to Dubai.
"I literally haven't stopped thinking about him since last week, when I remembered that he had returned to Kathmandu and asked for a flight to Dubai. What is he doing and where is he if he survived the robbery?
Dr. Crozier thinks that because her brother was "on his own," he was "vulnerable" to robbers. It might have "triggered a breakdown," in her opinion.
The computer science graduate traveled for a year, including a trip to Nepal.
Dr. Crozier looked for information about her brother for ten months. She conducted interviews with locals and learned that he had visited Nepal's Arun Valley before flying back to Kathmandu at the beginning of April 2003.
After looking to book a flight to Dubai, the investigation was over.
She says it was "really awful" to realize we hadn't found him while flying home.

Finding solutions seems "suddenly urgent," according to Dr. Crozier, as their father Anthony's health is declining and exactly 20 years have passed since his last contact with them.
She claims that it would be tragic and heartbreaking if Dad passed away unaware.
"I'm hoping he has a life. He doesn't even have to get in touch with us; just let us know he's still alive, especially for dad. ".
Dr. Crozier, a mother herself, claims that the experience of having her brother go missing has helped her see things in a different light.
"It really helps you realize and value the important things in life. Everything else is just a minor detail; the only thing that matters is that my kids are safe.
"The entire family has found it difficult. ".
Anyone with information about her brother's disappearance or who may have seen her brother is welcome to contact Dr. Crozier.
She claims that distinctive features like a sizable Chinese dragon tattoo on his back may help people recognize him.
She says, "I do have some hope. "You do occasionally hear reports of people being located.
. "