How old are the characters in the sad story?

I don't have a definite answer. The story could have the sad boy be of any age. It could be a young child or a pre-teen. Without more context, it's impossible to know for sure.

I have no idea. The story didn't mention his age.

I have no clue. The author might have focused on other aspects rather than specifying the age.

Once there was an old man. He used to live alone in a small, dilapidated house. His children had moved to the city long ago and rarely visited him. Every day, he would sit by the window, looking out at the empty street, waiting for someone to come. He had so many memories but no one to share them with. His only companion was an old dog that was also getting weak with age. It was a truly sad existence of loneliness and longing for family.

Marilyn Monroe is a key figure. Her story is full of sadness. She was used by the Hollywood system and had a hard time in her personal relationships. Then there's Charlie Chaplin. He had his own set of problems, including issues with the authorities over his political views which led to him being exiled from the US at one point.

There was an old woman who lost her only son in a war. She was left all alone in a small, dilapidated house. Every day, she would sit by the window, looking out at the road, hoping for his return. Her days were filled with memories of him, and the sadness of his absence made her cry every night.

The ages of the boy and the girl in the sad story could be anything. It depends on how the author chose to describe or not describe their ages.

Once there was an old man. He lived alone in a small, dilapidated house. His children had all moved away and rarely visited him. He spent his days sitting on his creaky porch, looking at the empty street, reminiscing about the days when his family was around and his life was full of laughter. He felt so lonely and sad, with only his memories to keep him company.

The story could be about the old fisherman who has lost his passion for fishing due to various setbacks and is now reflecting on his past. Maybe he's also dealing with a lack of support from his community.

I recommend "The Age of Warships: I Choose to Build a Stellar-level Giant Ship" by the author, Nuclear Powered Keyboards. The entire world had descended to another world. To survive in the sea world, the warship and talent were random. The protagonist, Ye Fei, was 25 years old, a Cancer. At the beginning, he had awakened the SSS-rank talent,"Infinite Fusion." Others were still struggling, but he had already fused the warship with various things, even fusing stars as energy sources. The warship equipment was super powerful. Although the overall plot wasn't very dramatic, it had a good imagination and was worth reading. "Reborn in the 80s" was an urban novel written by Piglet. The singer was reborn into an ordinary family 25 years ago, showing all aspects of life after the 80s. Wuxia: The Rise of the Supporting Character System, the work of the Jade Palace's Great Green Bull. After Lu Feng transmigrated and was placed under house arrest for five years, he had a system that allowed him to draw Character Summon Cards to change his identity and abilities. "The Umbrella Company of the American and Manga World", written by Goat Dafei. The protagonist became the successor of the umbrella in the Marvel world. He changed his strategy under pressure. The character was successfully created. The plot was good, but the updates were slow. Struggle in the Parallel Era, composed by Qu Sheng. After Yu Sui became a rich and beautiful woman, she went to the parallel world and became an illegal household. She could only fight again. "Hugging You in the Wind of the City" was equally exciting. Everyone was welcome to click and read it!