Despite being an inevitable part of life, there's so much about it we have yet to understand. And it's not just what happens after death that remains a mystery, but according to medical professionals, what often happens right before it is just as mystifying.

A hospice nurse identified an unexplained phenomenon that happens to people right before they die.

Julie McFadden has a Bachelor’s degree in Nursing and is a registered nurse who worked in an ICU for over a decade before becoming a hospice nurse, a position she's held for the last five years. Under the TikTok username @hospicenursejulie, McFadden shares experiences she has working in hospice care, tackling taboo subjects like death and dying in hopes of spreading awareness about how our bodies take care of us and alleviating anxieties people may have about dying.

Despite her vast knowledge on the subject, McFadden shared one phenomenon that she often sees with her patients that science has yet to explain.

“Here’s one phenomenon that happens during the death and dying process that medical professionals, like myself, cannot explain,” McFadden said in the video, referring to what she called "the rally," which is "when someone is really sick and almost towards actively dying, meaning dying within a few days, and then suddenly they look like they are ‘better'."

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They’ll start walking, talking, eating and doing other things that make people think that maybe they were never sick in the first place.

“They act like their old selves, they have a little more of a personality, king of laughing, talking, joking,” she explained. “But then, usually, they die within a few days after this, sometimes even that night.”

As an example of "the rally," several people in the comments referenced an episode of the hit TV Show Grey’s Anatomy during which Mark Sloan, one of the main characters in the show, woke up after becoming unresponsive following a plane crash. 

According to McFadden, "the rally" happens to around a third of the patients in hospice care, and it’s so common that they educate the families beforehand that this might happen “so it doesn't devastate them when they suddenly pass after doing so well for a few days."

'The rally' is also known as 'terminal lucidity.'

German researcher Michael Nahm has been studying the phenomenon and seeks to find out more about what he calls “terminal lucidity.” According to his studies, people have been reporting the phenomenon for over 250 years — 84 percent of those who experience it die within the week, with half of that dying that very day.

It’s become a medical mystery that many tie into their spiritual beliefs, since the idea that brains that are severely damaged could easily return to a state of “normalcy” is scientifically impossible.

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Dying patients may also see dead loved ones.

Another phenomenon that McFadden talks about that patients near death sometimes experience is seeing loved ones who've already passed on.

"It usually happens a month or so before the patient dies, they start seeing dead relatives, dead friends, old pets that have passed on, spirits, angels, that are visiting them and only they can see them,” she explained. “Sometimes it's through a dream, sometimes they physically see them, and they'll actually ask us 'do you see what I’m seeing.’”

Once again lending to the spirituality of what happens beyond the grips of life, many people see this as a way people are comforted before passing on and joining their loved ones who have left before them.

"They're usually not afraid, it's usually very comforting to them and they usually say they're sending a message like 'we're coming to get you soon' or 'don't worry, we'll help you.' Most people love this, they're very comforted by it, it's not scary to them," she added.

In another video, McFadden talks about how her experiences have opened her eyes to the concepts surrounding death and how they’ve made her believe that we continue living after we pass, and it’s not hard to see why.

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Isaac Serna-Diez is a writer who focuses on entertainment and news, social justice, and politics.