Over the years, Greys Anatomy has featured a number of controversial relationships. From George and Olivia to Owen and Amelia, the show creators have certainly put together some interesting pairings. But over a decade later, one of the most talked-about relationships is that of Izzie Stevens and her patient Denny Duquette.

The affair between Izzie and Denny was short but intense. And its tragic ending was one that left everyone surprised. But perhaps even more surprising was the $8 million check Denny left his fianc upon his death. Now, fans want to know, did we ever find out why Denny had all that money anyway?

From the beginning, it was clear the relationship between the young intern and her heart patient was doomed for disaster. Denny was a longtime patient at Seattle Grace and immediately smitten at first sight of the beautiful Dr. Isobel Stevens. And while Izzie initially tried to refrain from any sort of romantic relationship, she quickly fell head over heels.

Sadly, Denny had a bad heart. And when he lost his chance at a transplant, Izzie tried to steal one for him by cutting his LVAD wire. This decision ultimately led to the patients death and one of the most heartbreaking scenes in Greys Anatomy history.

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No one could have expected what would come next in the days that followed Dennys death. Amidst her grief over her dead fianc, Izzie was surprised by a visit from Mr. Duquette, Dennys father. But Mr. Duquette wasnt just there to meet the woman his son so quickly fell in love with, he was there to deliver a gift. As it turns out, one of Dennys final actions was to ensure his fianc received an $8.7 million check upon his death.

That check became everything central to Izzies storyline. It was the last piece that remained of Denny, proof that Izzie had not moved on, and who could forget how it almost became a part of breakfast. While Izzie initially struggled with what to do with the nearly $9 million check, she ultimately decided to use it to start the Denny Duquette Memorial Free Clinic.

Denny would live on through the people helped by the clinic.

Dennys gift went on to help hundreds of people who visited Seattle Grace, but in the midst of the tragedy that followed Dennys death, not many fans stopped to question exactly where this money came from. A recent Reddit thread brought up the issue again with one user asking, What on Earth did [Denny] do to make $8.7 mil by his mid-30s?

As other users pointed out, his medical bills certainly could not have been cheap and Denny never mentioned anything about being rich. Was it savings? Good investments? There was one clue that may have hinted at where the money came from.

When Mr. Duquette visited Izzie, what he really wanted to know is how the doctor got her patient to propose to her on the day he died. He jumped straight to the point, asking, Did you think that Denny would pay for everything? This implies the money wasnt any sort of insurance policy, but rather, money Denny had all along.

So, no. Fans never found out where Denny got all his money. But as we have all seen, Greys has brought this character back before. Theres always the possibility that one day the ghost of Denny will return and with that, well find out more about his past.

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'Grey's Anatomy': Did We Ever Figure Out Why Denny Had $8 Million to Give to Izzie? - Showbiz Cheat Sheet