After the airing of the latest episode of "This Is Us," more and more fan theories about the death of Jack have sprung up. In the most heartbreaking one yet, the death of the patriarch is now being connected to another death that happened in the recent episode.

To recap, Randall's biological William passed away. It was something that was inevitable as his cancer could no longer be cured. The father and son were the only ones prominently featured in what could be the most emotional episode of the hit series yet.

San Diego Entertainer reports that more of William's past was revealed. He was apparently a musician who left his band to take care of his dying mother. The scenes between William and his mother mirrored the present scenes of Randall caring for his now dying father.

Randall was with him comforting him during this time. What started the latest theory was his own words in a previous episode when he said that his father should have a nurse by his side always, as he cannot die when no one is looking.

US Magazine explained that the line seems to have come from a deep-seated fear from Randall and that he could have been thinking of Jack's death. While many viewers already know that Jack would die in the future, there are still many speculations as to how he will die.

Fans now theorize that Jack could have died alone which resulted to Randall making sure that his biological father will not die the same way his adoptive father did. This theory is the most heartbreaking one yet, as Jack's character showed him as a very loving father and husband, and dying alone would just be tragic.

Do you think that there is truth to this theory about Jack's death on "This is Us?" What are your own theories about his demise? Share your thoughts and comments below.