What is sound, and it is not less
Four things, all from the strongest material there is.
A Muslim whose children die before puberty is promised Paradise by Allah out of His mercy towards them. In another report a woman whose children died would be screened by them from the Fire, and when it was asked whether two would do, the answer was that two would.
There is a report on one whose child dies and who resigns himself calmly to what Allah has decreed, and the chapter it sits under is titled for the merit of exactly that person.
And there is the instruction that the prayer is offered over a miscarried child, and that forgiveness and mercy are asked for its parents. Read the second half of that again. The tradition does not only account for your child. It names you.
The sentence that goes with all of this is the one you say rather than the one that is said at you. Indeed we belong to Allah, and indeed to Him we return. It belongs in your mouth. When somebody else uses it to close the conversation, that is a misuse of it, not a fault in you for finding it cold.
Qur’an and Sunnah
وَلَنَبۡلُوَنَّكُم بِشَيۡءࣲ مِّنَ ٱلۡخَوۡفِ وَٱلۡجُوعِ وَنَقۡصࣲ مِّنَ ٱلۡأَمۡوَٰلِ وَٱلۡأَنفُسِ وَٱلثَّمَرَٰتِۗ وَبَشِّرِ ٱلصَّٰبِرِينَ
We shall certainly test you with fear and hunger, and loss of property, lives, and crops. But [Prophet], give good news to those who are steadfast
Qur’an 2:155
ٱلَّذِينَ إِذَآ أَصَٰبَتۡهُم مُّصِيبَةࣱ قَالُوٓاْ إِنَّا لِلَّهِ وَإِنَّآ إِلَيۡهِ رَٰجِعُونَ
those who say, when afflicted with a calamity, ‘We belong to God and to Him we shall return.’
Qur’an 2:156
أُوْلَٰٓئِكَ عَلَيۡهِمۡ صَلَوَٰتࣱ مِّن رَّبِّهِمۡ وَرَحۡمَةࣱۖ وَأُوْلَٰٓئِكَ هُمُ ٱلۡمُهۡتَدُونَ
These will be given blessings and mercy from their Lord, and it is they who are rightly guided
Qur’an 2:157
Narrated Abu Sa`id:The women requested the Prophet, "Please fix a day for us." So the Prophet (ﷺ) preached to them and said, "A woman whose three children died would be screened from the Hell Fire by them," Hearing that, a woman asked, "If two died?" The Prophet (ﷺ) replied, "Even two (would screen her from the (Hell) Fire. " And Abu Huraira added, "Those children should be below the age of puberty
Sahih al-Bukhari 1249graded sound, sahihaynfull report
Narrated Anas:The Prophet (ﷺ) said, "A Muslim whose three children die before the age of puberty will be granted Paradise by Allah due to his mercy for them
Sahih al-Bukhari 1248graded sound, sahihaynfull report
Abu Huraira reported Allah's Apostle (ﷺ) as saying:Anyone amongst the Muslims, three of whose children die, and he resigns himself calmly to the will of God, Fire will not touch him but for the fulfilment of the oath
Sahih Muslim 2632graded sound, sahihaynfull report
Narrated Al-Mughirah ibn Shu'bah: (I think that the people of Ziyad informed me that he reported on the authority of the Prophet (ﷺ): A rider should go behind the bier, and those on foot should walk behind it, in front of it, on its right and on its left keeping near it. Prayer should be offered over an abortion and forgiveness and mercy supplicated for its parents
Sunan Abi Dawud 3180graded sound, albanifull report
Translation: M.A.S. Abdel Haleem, The Qur'an, Oxford University Press, 2004.