John Ritter had spent decades making people laugh, but on September 11, 2003, the beloved Three’s Company star suddenly became ill while working on the set of 8 Simple Rules.
He was only 54.
What initially appeared to be a heart attack was actually something very different: an acute type A aortic dissection, a tear in the wall of the body’s largest artery. Ritter died that night.
Twenty-three years later, his widow, Amy Yasbeck, and his children are still making sure that what happened to John doesn’t remain simply a Hollywood tragedy. In September 2026, around what would have been the actor’s 78th birthday, his family renewed its campaign to educate people about aortic disease — including the importance of recognizing symptoms and understanding whether the condition might run in a family. (johnritterfoundation.org)
The Day John Ritter Went to Work and Never Came Home
September 11, 2003 began as an ordinary working day for Ritter.
He was starring as Paul Hennessy on ABC’s 8 Simple Rules… for Dating My Teenage Daughter, alongside Katey Sagal and a young Kaley Cuoco. During rehearsals, however, Ritter began feeling ill.
He was taken to a nearby hospital.
Doctors initially treated him for a suspected heart attack. His condition deteriorated rapidly, and the actual problem was ultimately identified as a type A aortic dissection. Ritter died later that evening. (johnritterfoundation.org)
The loss stunned his family, his colleagues and millions of viewers who had grown up watching him.
For Amy Yasbeck, however, grief eventually became a mission.
Only weeks after John’s death, she established the John Ritter Foundation for Aortic Health, dedicated to research, education and awareness surrounding thoracic aortic aneurysms and dissections. (johnritterfoundation.org)
More than two decades later, she’s still doing that work.
The Condition Can Develop Quietly
One reason the Ritter family continues talking about aortic disease is that an aneurysm can exist without obvious symptoms.
The aorta is the body’s main artery, carrying blood from the heart to the rest of the body. An aortic aneurysm occurs when part of its wall becomes enlarged or weakened. An aortic dissection happens when the inner layer tears, allowing blood to enter the wall of the artery and separate its layers.
According to the John Ritter Foundation, many thoracic aortic aneurysms cause no symptoms until they become very large or a dissection occurs. (johnritterfoundation.org)
Once an acute dissection begins, however, it becomes a medical emergency.
The foundation says the most common warning symptom is the sudden onset of severe pain, particularly in the chest or back. (johnritterfoundation.org)
That distinction has become central to the family’s message: understanding a person’s risk before an emergency occurs can make an enormous difference.
Then the Ritter Family Discovered Something Else
After John’s death, questions began emerging about whether aortic disease might exist elsewhere in his family.
That possibility changed the way his relatives approached their own health.
The John Ritter Foundation now emphasizes family screening because thoracic aortic disease can cluster in families. According to its screening guidance, roughly 20% of people with a thoracic aortic aneurysm or dissection have a first-degree relative who also has aortic disease. (johnritterfoundation.org)
First-degree relatives include parents, siblings and children.
That means John’s death wasn’t something his children could simply regard as an isolated medical event.
They needed to know their own risk.
Jason Ritter Says the Children Are Screened Regularly
John’s eldest son, actor Jason Ritter, is now 46 — only eight years younger than his father was when he died.
And John’s death has profoundly shaped how Jason thinks about his own health.
Speaking in September 2026, Jason revealed that he and his siblings undergo regular scans because of their family history. (People.com)
John had four children: Jason, Carly, Tyler and Noah.
The screenings are intended to detect possible aortic abnormalities before they become emergencies.
The foundation recommends that relatives considered at risk undergo appropriate imaging of the aorta. Depending on the individual situation, that may involve an echocardiogram, CT angiography or magnetic resonance angiography. Genetic counseling and genetic testing can also play a role in families affected by thoracic aortic disease. (johnritterfoundation.org)
For Jason, those checkups unexpectedly revealed an entirely separate health issue.
One of Jason’s Routine Scans Led to an Unexpected Diagnosis
Jason told People that during one of his health screenings, doctors discovered that he had type 1 diabetes.
He said the diagnosis came approximately two years ago.
Today, he manages the condition with insulin and an insulin pump and says becoming a father has given him another reason to take his health seriously. He shares a seven-year-old daughter with actress Melanie Lynskey. (People.com)
The experience seems to have reinforced something the Ritter family has spent years advocating: information discovered early can change what happens next.
Jason has also become increasingly aware of another connection with his father.
As he gets older, he says he sees more of John in himself.
He notices it in his facial expressions, mannerisms and even moments during performances. And he remains deeply touched when strangers tell him how much happiness his father brought into their lives. (People.com)
That makes the family’s health work particularly personal.
Jason isn’t merely promoting an organization carrying his father’s name.
He’s approaching the age his father never had the opportunity to reach.
Amy Turned Her Husband’s Death Into a Mission
Amy Yasbeck married John in 1999 after the two had known each other for years and worked together.
When he died four years later, their life changed in an instant.
But Amy eventually transformed the loss into something designed to help other families avoid experiencing the same thing.
The John Ritter Foundation’s mission now extends beyond basic awareness. It supports education, research, advocacy and resources for families affected by thoracic aortic disease. (johnritterfoundation.org)
In September 2026, the foundation held its annual Evening From the Heart gala in Los Angeles, bringing together John’s relatives, friends and former colleagues.
Amy was there.
So were members of the Ritter family.
The gathering took place during Aortic Dissection Awareness Week, held September 13–19 this year. (johnritterfoundation.org)
For Amy, events like these keep John’s memory attached to something potentially lifesaving.
One Family Member’s Screening Already Made a Difference
The Ritter family’s experience illustrates why they have become so focused on screening relatives.
John’s brother, Tom Ritter, was found to have an aortic aneurysm after John’s death, according to accounts of the family’s subsequent medical investigation. That discovery allowed doctors to intervene before he experienced the same catastrophic event that killed his brother. (New York Post)
It was a powerful example of what Amy had begun advocating.
John’s death could not be undone.
But understanding what happened to him could potentially change the outcome for somebody else.
That is why the foundation encourages people with a family history of thoracic aortic aneurysm or dissection to discuss screening with a clinician. (johnritterfoundation.org)
The Symptoms Can Resemble a Heart Attack
One of the most important lessons from Ritter’s death is that an aortic dissection can initially resemble other emergencies.
The foundation notes that a dissection can mimic a heart attack. Because heart attacks are much more common, distinguishing between the two can sometimes be challenging during an emergency evaluation. (johnritterfoundation.org)
The symptoms that warrant urgent medical attention can include sudden, severe pain in the chest or back, particularly pain that feels dramatically different from anything experienced before. (johnritterfoundation.org)
Imaging is critical when an aortic problem is suspected.
The foundation notes that CT, MRI and certain forms of echocardiography can identify aortic aneurysms and dissections, whereas an ordinary chest X-ray or ECG cannot by itself rule out a dissection. (johnritterfoundation.org)
For the Ritter family, that isn’t abstract medical information.
It comes directly from what happened to John.
His Former Co-Stars Haven’t Forgotten Him Either
The 23rd anniversary of Ritter’s death brought another wave of memories from the people who knew him.
Joyce DeWitt, who starred opposite him on Three’s Company, recently remembered the extraordinary physical chemistry they shared while playing Janet Wood and Jack Tripper.
She described their connection as almost instinctive — a kind of “kinesthetic communication” that allowed them to react physically to one another while performing the elaborate comedy that made the sitcom famous. (EW.com)
Henry Winkler also recently revealed that he still owns an unexpectedly poignant object from Ritter’s final day: an unopened water bottle from the 8 Simple Rules set.
Winkler had been guest-starring on the show when Ritter became ill. More than two decades later, he still keeps that bottle as a reminder of his friend. (EW.com)
Those stories help explain why Ritter’s death still feels unusually vivid.
For audiences, he was Jack Tripper.
For his colleagues, he was the man standing beside them only hours before everything changed.
John Would Have Turned 78 This Year
John Ritter was born September 17, 1948.
He would have celebrated his 78th birthday in 2026. (johnritterfoundation.org)
Instead, his family marked another birthday without him by talking about the disease that took him.
There is something bittersweet about the legacy that emerged.
Ritter became famous by making people laugh. His performance as Jack Tripper earned him an Emmy and a Golden Globe and helped turn Three’s Company into one of television’s defining sitcoms. (johnritterfoundation.org)
But after his death, his name became connected to something entirely different.
Aortic awareness.
Family screening.
Recognizing symptoms.
Knowing your family history.
And acting quickly when something feels seriously wrong.
Twenty-three years after Amy Yasbeck lost her husband and Jason Ritter lost his father, they are still repeating that message.
They cannot change what happened on September 11, 2003.
But every person who recognizes an aortic emergency sooner, every family that discovers an aneurysm through screening, and every life that can be protected because someone knew what to look for gives John Ritter’s story another ending.
That is why his family is still, as they put it, “ringing the alarm.” (johnritterfoundation.org)
For more on the Ritter family, check out how John Ritter’s Sons Are Now 46 and 41 – Fans Can’t Get Over How Much Jason and Tyler Look and Even Sound Like Their Famous Dad and then take a peek at why Katy Perry, 41, Turns Heads in Sculptural White Gown Beside Justin Trudeau – but the Dress Sparks a Wave of Pregnancy Speculation.
