A 2-year-old United Kingdom girl had a near-death experience after doctors — by chance — found a penny-sized lithium battery lodged in her throat.

Elsie-Rose’s mother, Kristy Duffy, of Barnsley, South Yorkshire, scheduled a doctor’s appointment for her daughter on Aug. 29. The young girl had been complaining of stomach aches for “several months,” Duffy told South West News Service (SWNS), a British news agency.

"On the night before her appointment she had said 'Elsie [is] feeling sick,’ but I just put it down to the continuing problem — which turned out to be constipation — I did not know she had swallowed a battery,” the mother said. "It was by a stroke of absolute luck that her hospital appointment was the next day."

RHODE ISLAND BOY, 4, WEIGHS NEARLY TWICE AS MUCH AS AVERAGE KID HIS AGE DUE TO RARE CONDITION

The following day, Duffy took Elsie-Rose to Sheffield Children's' Hospital in South Yorkshire. When performing an X-ray, doctors noticed something unusual in the young girl’s esophagus near the chest area. At first, it appeared to be a penny — but further examination revealed it was something more dangerous: A small lithium battery.

The chemicals from the battery were burning a hole in the Elsie-Rose’s throat, meaning she required surgery immediately. The 2-year-old was rushed to Leeds General Infirmary for emergency surgery, Duffy told SWNS.

“The surgeons told me her chances of survival were like her walking across a motorway without getting hit by a car. I couldn’t believe it,” she recalled. “They told me to give her ‘one last kiss’ and although I was devastated and in shock at the time, I just did my best to be strong for her.”

Thankfully, the surgery went well; doctors successfully removed the battery from her throat. Elsie-Rose remained in intensive care for a few days following surgery.

Though button batteries can pass through the gut without issue, “in recent years the number of debilitating or fatal battery ingestions has dramatically increased,” the National Capital Poison Center states.

“Fatalities and cases with severe esophageal or airway burns and subsequent complications have been reported, even in patients who initially have no symptoms after swallowing the battery,” it continues, noting “These disastrous outcomes occur when batteries get stuck in the esophagus, usually in small children.”

If the swallowed battery is not removed within a matter of hours, it can cause burns to the esophagus and other “life-threatening complications.”

It’s not clear how long the battery was inside of Elsie-Rose before it was removed.

DEADLY MOSQUITO-BORNE EEE VIRUS OUTBREAK IN MASSACHUSETTS MAY BE CAUSED BY THIS, EPIDEMIOLOGIST SAYS

The surgeon who treated the toddler told Duffy her child was “lucky to survive something she should not have survived.''

"I can't believe I nearly lost my little girl. This could have had a very different outcome,” she continued, adding she’s not sure where Elsie-Rose found the battery. It may have come from one of her siblings’ toys, she noted.

CLICK HERE TO GET THE FOX NEWS APP

“She’s not the type of toddler who puts items in her mouth usually so I didn’t know what had happened. In no way would I have thought batteries would be a good thing to swallow, but never would I have thought that it could kill a child,” she said. "It is so important that parents keep these out of reach of children."