Quran At-Tawbah 9:113
مَا كَانَ لِلنَّبِيِّ وَٱلَّذِينَ ءَامَنُوٓاْ أَن يَسۡتَغۡفِرُواْ لِلۡمُشۡرِكِينَ وَلَوۡ كَانُوٓاْ أُوْلِي قُرۡبَىٰ مِنۢ بَعۡدِ مَا تَبَيَّنَ لَهُمۡ أَنَّهُمۡ أَصۡحَٰبُ ٱلۡجَحِيمِ ١١٣
Translation
It is not for the Prophet and those who have believed to ask forgiveness for the polytheists, even if they were relatives, after it has become clear to them that they are companions of Hellfire.