Will a son bear the burden of his mother's displeasure with him if that happened unintentionally on his part and she died, and will his repentance be accepted and will he attain the pleasure of Allah and his parents after their death, especially if he regrets and repents, and will Allah forgive him for filial disobedience despite the hadiths that mention the non-acceptance of the disobedient person's deeds and his not entering Paradise?

Disobeying one's parents is a major sin, especially disobeying the mother. However, Allah overlooks sins committed by mistake, or out of forgetfulness, or under duress. Moreover, sincere repentance erases all previous sins, even if they were major sins or the greatest polytheism (shirk akbar). Regretting a sin is repentance, and he who repents from a sin is like one who has no sin. Among the ways to show filial piety to parents after their death are: praying for them, seeking forgiveness for them, fulfilling their pledges, maintaining kinship ties that are only connected through them, and honoring their friends. Allah forgives all sins for whom He wills, except for the greatest polytheism if its perpetrator does not repent from it. Therefore, the sinner must repent, seek forgiveness, and maintain kinship ties to draw closer to Paradise and distance himself from Hellfire.