(CNN) Three fathers who were separated from their young children when they tried to migrate to the US want millions of dollars in compensation from the US government for the toll the months of separation took on their families.

The Southern Poverty Law Center (SPLC) and law firm Covington & Burlington filed administrative claims Thursday seeking damages from the US government on behalf of three men who were separated from their children at the border. The separation caused lasting harm for the families, the advocacy group and law firm said in a news release.

The filings describe children who cry in the night, refuse to eat and are fearful of going out, and parents struggling with guilt and anxiety.

"Thousands of children, parents and entire families will suffer the rest of their lives as a result of this administration's intentionally cruel family separations," said Michelle Lapointe, senior supervising attorney at the SPLC.

The claims are seeking $3 million in compensation per person, or a total of $6 million per separated family, the SPLC told CNN. If the government does not respond to the claims within six months, the fathers can go on to sue the government in federal court.

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