The Tool Desk
Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Brett Gardner’s 14-year-old son Miller’s cause of death was reported by Costa Rican authorities as carbon monoxide poisoning. Miller died on March 21, 2025, during a family vacation in Costa Rica. Toxicology testing reportedly found 64% carboxyhemoglobin saturation, which officials said was above the lethal threshold cited in their investigation.
The finding followed preliminary reports that considered food intoxication and asphyxiation. Authorities later reported that asphyxiation had been ruled out and that toxicology identified carbon monoxide poisoning as the cause of death.
Key takeaways
- Costa Rican authorities reported carbon monoxide poisoning as the cause of death of Miller Gardner, who was 14 when he died on March 21, 2025.
- Toxicology testing reportedly found a carboxyhemoglobin saturation of 64%, which Costa Rican officials said was above the lethal threshold they cited.
- Early reports considered food intoxication and asphyxiation, but authorities later reported that asphyxiation had been ruled out and identified carbon monoxide poisoning.
- Miller died while vacationing with his family at the Arenas Del Mar Beachfront & Rainforest Resort in Manuel Antonio, Costa Rica.
- The Gardner family filed a federal negligence and wrongful-death lawsuit on March 20, 2026; the complaint’s allegations have not been adjudicated.
What was Brett Gardner’s son Miller’s cause of death?
Costa Rican authorities reported that Brett Gardner’s 14-year-old son Miller died from carbon monoxide poisoning during a family vacation in Costa Rica on March 21, 2025. Toxicology testing reportedly found 64% carboxyhemoglobin saturation, a result Costa Rican officials said exceeded the lethal threshold cited in their investigation.
The cause was reported after authorities reviewed toxicology results and moved beyond earlier preliminary theories. CBS News, citing the Associated Press, reported the Costa Rican confirmation on April 3, 2025.
Free tools Windows power users keep installed
One-click scans. No signup required.
#1 Best Overall
What did the toxicology report say?
The key finding was a carboxyhemoglobin saturation of 64%. Carboxyhemoglobin forms when carbon monoxide binds to hemoglobin, reducing the blood’s ability to carry oxygen. According to Costa Rica’s Judicial Investigation Agency in 2025, the reported result was 64%; officials said concentrations above 50% are considered lethal in the context of their report.
Randall Zúñiga, director of Costa Rica’s Judicial Investigation Agency, said: In the carboxyhemoglobin test, a saturation level of 64 percent was found.
ABC News reported the toxicology finding and the authorities’ explanation on April 3, 2025.
The 64% figure and the officials’ description of the threshold are being attributed to Costa Rican investigators. No independent testing or first-hand investigation is presented here.
Rank #2
How did the reported cause of death change during the investigation?
Early accounts did not identify a confirmed cause of death. Initial official reporting discussed possible food intoxication and asphyxiation. A later update said asphyxiation was preliminarily ruled out because investigators observed no macro-level abnormality in the respiratory tract. Subsequent toxicology reporting identified carbon monoxide poisoning.
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Fix the driver behind crashes, sound loss and screen glitches3Repair Windows errors before they cause bigger problemsThe progression matters because early versions of the story may still appear in search results. The available reporting does not establish that food poisoning caused Miller’s death. ABC News’ report on the preliminary investigation described the change concerning asphyxiation, while later reporting documented the toxicology result.
When and where did Miller Gardner die?
| Date | What was reported |
|---|---|
| March 21, 2025 | Miller Gardner died during a family vacation in Costa Rica. |
| March 23, 2025 | Brett and Jessica Gardner announced their son’s death in a statement released through the New York Yankees. |
| March 24–26, 2025 | Preliminary accounts considered food intoxication and asphyxiation; asphyxiation was later reported as ruled out. |
| April 2–3, 2025 | Costa Rican authorities reported the toxicology finding and carbon monoxide poisoning as the cause of death. |
| March 20, 2026 | The Gardner family filed a negligence and wrongful-death complaint in federal court in Pennsylvania. |
The family was staying at the Arenas Del Mar Beachfront & Rainforest Resort in Manuel Antonio. The resort’s identity and the reported toxicology finding were covered by CBS News and the Associated Press.
Rank #3
Was the Costa Rica resort legally responsible for Miller Gardner’s death?
The resort’s legal responsibility has not been established by a court. On March 20, 2026, the Gardner family filed a federal negligence and wrongful-death complaint against resort-related companies and individuals. The case is identified on the docket as GARDNER et al v. CALLAN et al, Civil Action No. 2:2026cv01830, in the U.S. District Court for the Eastern District of Pennsylvania. The federal docket records the filing and case number.
According to reporting on the complaint, the family alleges that an inadequately ventilated machine room exposed people at the resort to carbon monoxide. The complaint also alleges that the exposure caused Miller’s death and illness or injury to relatives. Those statements are allegations made by the plaintiffs, not findings by the court. The Associated Press reported the lawsuit’s allegations and procedural status.
The resort has disputed the account. The resort reportedly said the guest room did not contain lethal carbon monoxide and that elevated levels were found in an adjacent mechanical room. The available material therefore establishes a reported toxicology result and a pending civil dispute, but it does not establish legal liability.
What did Brett and Jessica Gardner say about their son?
Brett and Jessica Gardner announced Miller’s death on March 23, 2025, through the Yankees. The family statement said: Miller was a beloved son and brother and we cannot yet comprehend our life without his infectious smile.
CBS News reported the family’s statement.
What is carbon monoxide and how can people reduce the risk?
Carbon monoxide is an odorless, colorless gas that can cause sudden illness and death, according to the Centers for Disease Control and Prevention’s carbon monoxide guidance. Because people cannot reliably detect it by smell or sight, prevention depends on maintaining fuel-burning equipment appropriately and using alarms in the recommended locations.
The CDC recommends battery-operated or battery-backup carbon monoxide detectors near every sleeping area and says detectors should be replaced according to the manufacturer’s instructions or every five years. The U.S. Consumer Product Safety Commission recommends alarms on each level of a home and outside sleeping areas, regular testing, and annual battery replacement unless an alarm has a sealed 10-year battery. Readers should follow the instructions for the particular alarm they install.
For readers looking for a practical prevention step, official guidance recommends installing a carbon monoxide detector near sleeping areas and on each level of the home. A detector is a general safety measure, not evidence that a particular device was involved in or could have prevented Miller Gardner’s death.
Best Value
What is established and what remains unresolved?
| Established in the available reporting | Not established by the available reporting |
|---|---|
| Costa Rican authorities reported carbon monoxide poisoning as the cause of death. | That the resort was legally responsible. |
| Reported toxicology showed 64% carboxyhemoglobin saturation. | That food intoxication caused the death. |
| Miller died at age 14 on March 21, 2025, while in Costa Rica. | Any final court finding about the resort’s ventilation or liability. |
| The family filed a federal negligence and wrongful-death complaint on March 20, 2026. | Details beyond the reported allegations and the resort’s reported dispute. |
The most current reported cause of death in the supplied records is carbon monoxide poisoning based on Costa Rican toxicology reporting. The related civil lawsuit remains a pending dispute, and allegations in the complaint should not be treated as proven facts.
The Bottom Line
Costa Rican authorities reported that Miller Gardner died from carbon monoxide poisoning on March 21, 2025, after toxicology testing found 64% carboxyhemoglobin saturation. Earlier theories were preliminary, and the Gardner family’s 2026 lawsuit against resort-related defendants remains unresolved.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
