''This Is Us'' has jumped into another chapter of the Pearson family's extraordinary odyssey. Episode 4 of Season 3 brought Nick Pearson into the spotlight as that long-awaited Vietnam War scenery was there to steal the episode.

The entire episode was about us getting to know the whole context that eventually transformed Jack into that Jack Pearson many of us hold with high regard on our TV series characters list.

The narrative threads were also stretched out widely as the episode covered a significant time frame. It all starts with Nicky's birth on October 18, 1948, and culminates with the moment when Jack reunites with his brother in the Vietnamese war zone.

Why Jack and Nick went to war

According to vanityfair.com, the story of Jack and Nicky going out to war is a bit more nuanced than expected.

As it turned out, Nicky's birthday wasn't that lucky after all, as he got drafted to the Vietnam War. Let's not forget that scene when the clock was only two minutes before midnight when the whole birth procedure was done and dusted. Those two minutes are the cornerstone for the whole Pearson family, especially for Jack who would see his future choices all being made as a result of his little brother being born that day.

So, Nicky was drafted and later deployed to Vietnam. As he failed to accommodate, his behavior got sanctioned and he found himself in trouble.

And, as always, once he got news on this, Jack stepped in to save the day.

Jack Pearson was not drafted. He volunteered instead, choosing to go to a war everybody was running away from at that time. It was 1971 when Jack made this decision although he had a preexisting heart condition. According to an article published on usatoday.com, Jack was suffering from tachycardia.

As an avid viewer, one would easily make a connection between that and Jack dying from a heart attack. Let's not forget that Jack died due to a heart attack.

Well, Jack was willing to bend the rules so that his brother wouldn't be alone at war.

Other aspects are getting a new perspective

This episode and its journey back in time led us to some discoveries.

Jack's father used to be a decent man back in the days when he was not drinking at all. He had a strange relationship with his own father too, a man who was indeed a heavy drinker. That's perhaps the source of that drinking curse Jack kept telling Rebecca about when his own drinking issue came to surface.

Although he had a bad influence on Jack, his father taught him the most important lesson of his life, a piece of advice Jack would put first for the rest of his existence. His job, his only job was to look out after his little brother. And Jack Pearson did just that when he put his own life in a secondary place.