If my U.S. citizen child is a victim of a crime, can I (the undocumented parent) qualify for a U visa?
Possibly, yes. If your U.S. citizen child was the victim of one of the qualifying crimes, explained here, you as the undocumented parent may be able to apply as in indirect victim. In general, when the crime victim is a child (under 21 years old), his/her parents and minor siblings (under 18 years old) may be considered indirect victims. When determining possible indirect victims, USCIS will look at the age of the victim at the time the crime was committed.1 For the definition of an indirect victim, go to Who can be considered a "victim of crime" to be eligible for U visa status?
Note: If you (the undocumented parent) are applying as the indirect victim of the crime, this means that you (the parent) are the one listed as the indirect victim of the crime against your child on the law enforcement certification.
If you are applying as an indirect victim, you will be considered a “principal applicant,” and not a “derivative.” A “principal applicant” is a person who applies for an immigration benefit and from whom another person (usually a family member) may also receive lawful status as a “derivative” under immigration law.2 Note: Do not confuse derivatives (who do not have to meet all U visa status eligibility requirements but must show they are admissible) with indirect victims who do have to meet all U visa status eligibility requirements. As principal applicants, indirect victims will have to prove they meet the eligibility requirements for U visa status.
1 8 CFR § 214.14(a)(i)
2USCIS website – Glossary