By Claire Marshall
BBC News, Nuevo Laredo
The effect of the brutal drug war being waged in the northern Mexico border town of Nuevo Laredo is being felt in the United States.
Sleamaker set up the site after his step-daughter disappeared
More than 40 American citizens have been reported killed or kidnapped in the last year.
William Sleamaker has set up a website to unite the families of the missing, and to demand more information.
One of those missing is Yvette Martinez. On a photo on the Laredo's Missing website, she appears strikingly beautiful.
She has shining brown eyes, a wide, warm smile and her hair bounces in healthy curls around her face.
Her two children have not seen their mother for almost a year.
The 28-year-old crossed the border in to Mexico to see a concert in Nuevo Laredo with her friend Brenda Cisneros. They never came back.
"Their only crime was to be young and beautiful," says William Sleamaker, who is Yvette's stepfather, in the makeshift headquarters of Laredo's Missing - a friend's shop.
With no answers from either the Mexican or US governments, he set up the missing persons website to try to find information.
He believes that Yvette and Brenda are innocent victims of the vicious battle for dominance between two Mexican drug cartels.
Gerry went missing with his brother Sammy more than eight months ago
"These organisations are killing each other, and the low-level drug dealers who have lost income because of the chaos, have resorted to kidnapping to raise funds."
The faces of Gerry and Sammy are also on the website. Rosita Gonzalez' eyes fill with tears when she talks about her sons.
They crossed the border for a weekend away in Mexico eight months ago, and then disappeared.
"They didn't drink or smoke - they had no bad habits at all," says Rosita.
"I feel so bad not knowing what could have happened or why. It's a double pain as it's two of my sons.
"I'm afraid to go over there and ask for help when you don't know who you're dealing with."
Fight for justice
Mr Sleamaker intends to take the families' fight for justice all the way to Washington.
Banging his hand on the table, he says nothing has been done so far, "just because virtually all the victims have Spanish surnames".
"The war on drugs started in Colombia 15 years ago," he says.
"It has slowly been moving north and now it's knocking on the doors of the United States as we speak. And our government is not paying attention."
William Sleamaker's wife, Maria, is looking after Yvette's two daughters. She promised them she would hunt around the world for their mother.
She says she heard the eldest child praying before bedtime.
In her prayers, she said: "God, please bring Mummy back to us just one more time so that we can see her. Even if it's in a coffin."