The following contains spoilers from Young Sheldon Season 6, Episode 1, "Four Hundred Cartons of Undeclared Cigarettes and a Niblingo," which aired Thursday, Sept. 29 on CBS.

Without a doubt, the first four seasons of Young Sheldon were a comedy. The series' lighthearted tone was slightly at odds with its The Big Bang Theory source material, but fans gravitated nonetheless. The way that the series handled the problems around Sheldon was masterful, as he attempted to grow up and navigate the world as a boy genius.

However, Season 5 posited a change. Little by little, the problems affecting Sheldon were coming from inside his own family. In fact, some fans declared that Young Sheldon was becoming more of a family-based drama than a sitcom-style comedy. The Season 6 premiere, "Four Hundred Cartons of Undeclared Cigarettes and a Niblingo," continued the drama, but it also walked back one of the biggest developments from last season's finale. Here's what happened.

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Young Sheldon Ups the Family Drama

George Mary Cooper Young Sheldon

Young Sheldon Season 5 introduced many different problems for the Cooper family. It's been an ongoing plot, but George's potential affair with Brenda continued to loom on the horizon. That situation only got worse when George lost his job as the high school's football coach. Likewise, Season 5 teased a potential affair between Mary and Pastor Rob, which also became more complicated when Mary lost her job at the church.

The other major plot point from Season 5 was Georgie's relationship with Mandy, and that was trouble from the get-go. Mandy was 29, and Georgie was 17. So, when Mandy turned up pregnant, things fell apart, and that’s why Mary lost her job at the church. Unfortunately, the Season 6 premiere did nothing to reconcile Mary's issues with the church. In fact, Pastor Jeff's sermon about love was blatantly hypocritical, and Sheldon called him out on it point-blank.

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Why Sheldon Didn't Wear His The Flash T-Shirt

Young Sheldon Flash Tshirt

All of those issues were really starting to get to Sheldon in the Young Sheldon Season 5 finale. Between the onset of puberty and the added stress from his family's dilemmas, he developed a pimple. That, however, was only the outward signs of his inward fear of the future. Not knowing what to do, he asked Missy for advice, and she encouraged him to adopt a new, more mature look. So, for the first time, he ditched his bowtie and donned a The Flash t-shirt, saying, "I might look TOO cool." Fans instantly recognized the graphic tee as a classic part of Sheldon's The Big Bang Theory wardrobe and loved how it brought Sheldon closer to his TBBT self.

However, there was no sign of the Flash t-shirt in "Four Hundred Cartons of Undeclared Cigarettes and a Niblingo," and that was planned. Back in May, Young Sheldon co-creator Steve Molaro explained to TVLine that the Flash t-shirt wasn't supposed to be a full-on wardrobe change. Rather, it was supposed to be a signal: "When he feels like cutting loose, and experimenting with being a teenager, he’ll throw it on." So, the fact that Sheldon still rocked a bowtie for most of the episode shouldn't have been a surprise, but he will undoubtedly break out some more graphic tees as the season continues.

New episodes of Young Sheldon air Thursday nights at 8 pm on CBS.