Following Dua is good -

اَللَّهُمَّ اجْعَلْهُ فَرَطًا وَذُخْرًا لِوَالِدَيْهِ، وَشَفِيعًا مُجَابًا، اَللَّهُمَّ ثَقِّلْ بِهِ مَوَازِينَهُمَا، وَأَعْظِمْ بِهِ أُجُورَهُمَا، وَأَلْحِقْهُ بِصَالِحِ الْمُؤْمِنِينَ، وَاجْعَلْهُ فِي كَفَالَةِ إِبْرَاهِيمَ، وَقِهِ بِرَحْمَتِكَ عَذَابَ الْجَحِيمِ، وَأَبْدِلْهُ دَارًا خَيْرًا مِنْ دَارِهِ، وَأَهْلًا خَيْرًا مِنْ أَهْلِهِ، اَللَّهُمَّ اغْفِرْ لِأَسْلَافِنَا، وَأَفْرَاطِنَا، وَمَنْ سَبَقَنَا بِالْإِيمَانِ

Allahum-maj'alhu faratan wa dhukhran liwaalidayhi, wa shafee'an mujaaban. Allaahumma thaqqil bihi mawaazeenahumaa wa 'a'dhim bihi 'ujoorahumaa, wa 'alhiqhu bisaalihil-mu'mineen, waj'alhu fee kafaalati 'Ibraaheema, wa qihi birahmatika 'adhaabal-jaheem, wa 'abdilhu daaran khayran min daarihi, wa 'ahlan khayran min 'ahlihi, Allahum-maghfir li'aslaafinaa, wa 'afraatinaa wa man sabaqanaa bil'eemaan.

O Allah, make him a precursor, a forerunner and a treasure for his parents and an answered intercessor. O Allah, make him weigh heavily in their scales (of good) and magnify their reward. Make him join the righteous of the believers. Place him in the care of Ibrahim (As). Save him by Your mercy from the torment of Hell. Give him a home better than his home and a family better than his family. O Allah, forgive those who have gone (i.e. passed away) before us, our lost children (by death), and those who have preceded us in Faith.

Reference: See Al-Mughni, Lee Ibn Kudama, 3/416; See also Ad-Durusul Muhimmah Li ‘Ammatil Ummah, Lish Sheikh Abdil Aziz Ibn Abdillah Ibn Baz, Rahemahullah, p. 15.