Correct me if I'm wrong, I'm not a geneticist, but the logical reason for this sounds as simple as enriching the baby's DNA with that from the mother and father

Correct me if I'm wrong, I'm not a geneticist, but the logical reason for this sounds as simple as enriching the baby's DNA with that from the mother and father. Also only cells, which are our main building blocks, suffer from death. The death as we know it, is only affecting "bodily" species incl. single-celled life forms. DNA doesn't die, ever (given good conditions). That's why scientists can still extract DNA from animals which have been died thousands or millions of years ago.