A bottle of formula and a nap cost $18,000, according to a family whose son was treated at a San Francisco hospital after a head injury.

Vox.com reported that a family from South Korea was visiting the city in 2016 when their infant son fell off a hotel bed and hit his head. The baby reportedly never lost consciousness but was crying hysterically. So out of an abundance of caution, the family took him to Zuckerberg San Francisco General Hospital, the outlet reported.

Doctors quickly determined that 8-month-old Park Jeong-whan was fine. The family told the news site that the baby had some formula, took a little snooze and they got on with their vacation.

Two years later, the family said, they were handed the bill: $18,836.

“If my baby got special treatment, OK,” Jang Yeo-im, the baby’s mother, told Vox. “But he didn’t. So why should I have to pay the bill?”

The report pointed out that the family was charged more than $15,000 for “trauma activation.”

The fee, according to the report, is due to the hospital’s response to a potentially serious visit. These charges can range from $1,000 to $50,000, according to the report. One expert likened the charge to “the Wild West.”

Hospitals defend the charge by essentially saying it costs money to keep a good response team on hand.

“We are the trauma center for a very large, very densely populated area. We deal with so many traumas in this city — car accidents, mass shootings, multiple vehicle collisions,” a hospital spokesman told Vox. “It’s expensive to prepare for that.”