Jim Parsons's Lineage Deserves Many 'Best Dad Ever' Mugs

Caroline Kepnes
Yahoo! TV

Jim Parsons is all about the laughs on "The Big Bang Theory," but on "Who Do You Think You Are?" we get to see his serious side. (Fortunately, getting serious about his roots doesn't stop him from cracking jokes.) The knight of "Garden State" explains that he still misses his father, a charismatic man who supported Jim's interest in acting and died in a car accident several years ago, when he was only 51.

Jim is still in mourning; he raves about his father's loyal nature and capacity for friendship. Between the memories of his father and the family photos and the distant footage of Jim walking down the street, well, this episode is off to quite an emotional start, which is why we are so happy to meet Jim's incredibly buoyant mom, Judy. The woman is so cute with her pictures and her hairdo, and their relationship is just plain adorable. When Jim learns that one of his ancestors lived to be 91, he's psyched. "We got good blood," he quips to his mom. "Well, I do. This wasn't your blood." Ha!

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The Texas native then heads to New Orleans, Louisiana, to learn more, and boy, does he ever. Essentially, his paternal ancestor J.B. Hacker was a Dr. Quinn-type medicine man, an educated doctor at a time when a lot of so-called doctors were just snake oil salesmen who threw up a shingle to try to make a fast buck. "Some still do," Jim jokes. "I feel certain about this. I come from helpful people. I'm nowhere near a doctor, but it's nice to know that I'm related to one." And not just any old doctor: Dr. Hacker was the 55th person to graduate from the Medical College of Louisiana, which was established in 1834. And Hacker wrote extensively about the yellow fever epidemic of 1854 that killed 8,000 people in New Orleans. Jim marvels at Hacker's "real commitment to humanity."

Hacker died in a steamboat fire when he was only 44 years old. When Jim visits a replicate steamboat, he learns that these vessels were made out of wood at that time, which makes his death at 44 seem even more tragic. "That's only 4 years older than I am now," says Jim. "It's hard to hear of him putting so much work into this and have it end so suddenly and so soon. He couldn't have been more in the prime of his working." And the obituary that ran two weeks after Hacker's death was a beautiful tribute, so beautiful, in fact, that it reminds Jim of the response to his own father's passing. Jim reveals that he was stunned by how many people paid their respects to his father. "Are these the kind of qualities that are passed down?" he asks. "I don't know the answer, but it's not a far reach to say they are."

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In France, it's clear why producers saved this episode for last. Jim is a lively participant, funny and responsive, analytical and emotional. And, his family history turns out to be beautifully symmetrical. We already know that Jim's father encouraged and supported his artistic ambitions. And we learn that Jim's seven-times-great-grandfather supported his own son, Jim's six-times-great-grandfather, Louis Francois. Louis wanted to become an architect, and his father, a marble supplier, helped him achieve that goal. The parallels are not lost on Jim, who seems genuinely dumbstruck upon learning that one of his ancestors was an architect for the king of France in 1787.

Watch Parsons learn about his ancestor's prestigious career: 

"Wow," says Jim, before he even gets to Versailles, where he learns that he is standing in a church designed by his ancestor and considered a masterpiece. "I've said wow a lot, but I mean it." Jim describes the church as "elegant, classy and exciting." It's no wonder that Jim's six-times-great-grandfather won a scholarship to Rome, survived the French Revolution, was eventually admitted to the Royal Academy of Architecture, and (drumroll, please) hosted his friends Benjamin Franklin and John Adams at his home … as in, two of the greatest minds in world history. Jim believes that his ancestor wouldn't have realized his potential without his dad there to back him up.

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"I really don't know what I would have become without my father," he says as the episode draws to a close. You couldn't ask for a tidier ending. Jim Parsons learns that his paternal ancestor talked shop with world-famous titans, and he's still bringing it all back to his own dad. Talk about going out with a big bang. Well done, "WDYTYA." See you next year.

Check out episode photos from Season 4 of "Who Do You Think You Are?"