And if you are a Christian you can take comfort that your child is safe in Heaven with Our God, and you will be joined with them at some future date.
David knew he would see his child who died as an infant:
After King David's sin wherein his child was taken from him he knew that he would see his child again:
"22 And he said, While the child was yet alive, I fasted and wept: for I said, Who can tell whether GOD will be gracious to me, that the child may live? 23 But now he is dead, wherefore should I fast? can I bring him back again? I shall go to him, but he shall not return to me." 2 Samuel 12:22-23
David repented and God forgave:
"13 And David said unto Nathan, I have sinned against the LORD. And Nathan said unto David, The LORD also hath put away thy sin; thou shalt not die." 2 Samuel 12:13
Christian's children are safe until they reach the age of accountability:
14 For the unbelieving husband is sanctified by the wife, and the unbelieving wife is sanctified by the husband: else were your children unclean; but now are they holy. 1 Corinthians 7:14
If the wife is a believer and the husband is unsaved the unsaved is sanctified by the believing wife (sanctified, that is set apart unto God, not saved but sanctified. ) So if there is one believing parent then your children are clean and holy). Hopefully both are believing parents. But God counts your children as clean.
Your children are clean and holy and are in heaven.