David and Charlotte Willner were early Facebook employees who now work at Airbnb and Pinterest, respectively. “We can’t all be on the frontlines to help these families, but by supporting RAICES, we’re able to do something that just takes less than a minute, and collectively have an impact,” the Willners said in a statement shared with Quartz.

The power of fundraising on Facebook lies in just how easy it is for an individual user to donate, and, perhaps more importantly, how simple it is to spread the word about the cause across the network. Facebook, for example, encourages users to set up for their birthdays fundraisers for causes that they care about. As the RAICES fundraiser shows, it works particularly well when citizens hear about heartbreaking scenes on the US border involving small children in the news, and potentially on Facebook itself. The Willners’ fundraiser post spread organically, without any paid promotion, Facebook said.

That the couple who started it works in Silicon Valley surely helped as well. Both Facebook’s CEO Mark Zuckerberg and chief operating officer Sheryl Sandberg donated to the fundraiser.

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