MCALLEN – Homeland Security investigators are focused on family units coming into the U.S.

They’re working to figure out if the children are related to the people they are traveling with.

Border Patrol saw an increase in family units between the months of January and March – more than 25,000 family units attempted to enter the country.  

KRGV’s Christian Colón spoke with two parents who had to prove they were the legal guardians of their four girls with documentation.

“We couldn't enter without those documents. We could be accused of kidnapping or something like that,” explains the father.

An assistant special agent of Homeland Security Investigations explains the parents children must be biological parents or legal guardians, not members of their extended family.

Watch the video above for the full story.