(CNN) Six months after US officials separated them at the border, ICE put a 4-year-old girl on a plane to Guatemala this week so she could be reunited with her father.

But there was one major problem, according to advocates who worked on the case: The man didn't learn his daughter was coming until 30 minutes before her flight was set to land in Guatemala City.

He lives eight hours away -- too far to get there in time. After half a year apart from her father, the girl would have to spend another night in a shelter alone.

The case sparked fury and frustration this week from advocates working to help reunite children with deported parents. It's an example, they said, of a reunification effort that remains needlessly chaotic at times, even months after a federal judge ordered the US government to reunite the immigrant families it separated

"After what the US government has already done to these kids, it's beyond outrageous and inhumane," said Lisa Frydman, vice president of regional policy and initiatives for the nonprofit Kids in Need of Defense, which has been working with partners in Central America to facilitate reunifications.

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