I already read an account of an online friend whose adult son was detained because she gave birth to him at home. Apparently they're using any excuse they can to question citizenship. Via the Washington Post:

In some cases, passport applicants with official U.S. birth certificates are being jailed in immigration detention centers and entered into deportation proceedings. In others, they are stuck in Mexico, their passports suddenly revoked when they tried to reenter the United States. As the Trump administration attempts to reduce both legal and illegal immigration, the government’s treatment of passport applicants in South Texas shows how U.S. citizens are increasingly being swept up by immigration enforcement agencies.

Juan said he was infuriated by the government’s response. “I served my country. I fought for my country,” he said, speaking on the condition that his last name not be used so that he wouldn’t be targeted by immigration enforcement.

The government alleges that from the 1950s through the 1990s, some midwives and physicians along the Texas-Mexico border provided U.S. birth certificates to babies who were actually born in Mexico. In a series of federal court cases in the 1990s, several birth attendants admitted to providing fraudulent documents.

Based on those suspicions, the State Department began during Barack Obama’s administration to deny passports to people who were delivered by midwives in Texas’s Rio Grande Valley. The use of midwives is a long-standing tradition in the region, in part because of the cost of hospital care.

The same midwives who provided fraudulent birth certificates also delivered thousands of babies legally in the United States. It has proved nearly impossible to distinguish between legitimate and illegitimate documents, all of them officially issued by the state of Texas decades ago.