If your children receive Social Security survivors/disability benefits, that is income to them, not to you. You do not enter it on your tax return. Look at Box 2 of the SSA-1099 and you should see the child’s SSN.
If that is the only income a child has, then the child does not have to file or report it either.
If the child has enough other income to be required to file, then the child reports the SS on the child's return.