(CNN) In less than four days, a California couple has raised more than $6 million -- and counting -- through Facebook to help reunite undocumented families that have been separated at the border.

Charlotte and Dave Willner were inspired to start the campaign when they saw the viral image showing a frightened, crying 2-year-old girl looking up to the adults around her after crossing the border. The girl, who was with her mother and others, had rafted across the Rio Grande and the group was stopped in Texas by US Border Patrol agents.

A two-year-old Honduran asylum seeker cries as her mother is searched and detained near the U.S.-Mexico border.

"These aren't kids we don't have to care about. They're like our kids," Charlotte Willner told th e San Jose Mercury New s. "When we look at the faces of these children, we can't help but see our own children's faces."

The Willners originally started their fundraising campaign named "Reunite an immigrant parent with their child" on Saturday morning with the goal of $1,500. But soon their efforts went viral.

The couple chose to raise money for the Refugee and Immigrant Center for Education and Legal Services, or RAICES, a nonprofit in Texas that offers free and low-cost legal services to immigrants and refugees. The original goal of $1,500 was the minimum amount to cover bond fees for one person, according to RAICES.

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