During its run, the HBO series inspired both respect and controversy and spawned a variety of memorable characters. Based on the , , the show revolved around medieval-style political maneuvering with its primary focus on two families: . The Lannisters held the predominance of power, based in King’s Landing, and were known for secrets and backstabbing. Over the show's eight seasons, various kings and queens sat , including the third child of Jaime and Cersei Lannister, Tommen. He succeeded to the throne after his brother Joffrey was murdered, only to meet an untimely end in Season 6 when he leaped to his death from a window.
So why was Tommen’s death so largely ignored by his mother and biological father, after they heavily mourned the previous deaths of his siblings? If you study the family dynamics of the dysfunctional Lannisters it is not surprising that his mother Cersei disregarded her son’s death. She, while loving Tommen, viewed him as a pawn in her game. She sought to manipulate him to control Westeros, as she did with Joffrey. To her, his kind, quiet nature signaled weakness, something to be exploited to maintain her status as the power behind the throne.
She miscalculated her influence. Tommen, as the spare son, grew up bullied by his brother, being shunted to one side in favor of Joffrey, and the bond between mother and son was not as strong as she believed. Tommen turned away from his mother, in favor of his queen, Margaery Tyrell, a woman that utilized her influence over him through kindness. It precipitated a showdown between mother-in-law and daughter-in-law that escalated into a war of faith and led Tommen down the path of lessening his mother’s power. To Cersei, this was a betrayal, and fans of the show know that Cersei did not forgive betrayal. Tommen sealed his role as her adversary by threatening to relegate her to a forgotten footnote
Jaime’s reaction was harder to understand, but as with most things in his life, his sister likely motivated his muted reaction. Despite his initial shock, and knowing her volatility, Jaime placated Cersei and took his emotional cues from her. At that point, the last thing he wanted was to be her enemy. As well, because of the incestuous secret parentage, Jaime had limited involvement with his biological children and that tempered the closeness between father and son. Guilt, too, could have played a part; he once promised to spare his son the fate of his brother, yet they both ended up dead.
As for anyone else who might have mourned Tommen -- his wife, his sister, his grandfather -- they all died before him. He stood alone at the end, and Tommen’s choice of death over being king under his mother’s thumb was his last act of defiance against his parent. But Cersei never accepted defiance. She punished her son in the only way she had left: by refusing to acknowledge he meant something to her.