May have been better to have lost the child in that way than to have carried it to term and then discovered problems.

As far as why did death come to somebody so innocent, death comes for all of us. From the moment the “winning” spermatozoa punches through the other layers of the egg, death comes for that zygote. While the Time and place may be unknown, that zygote will, eventually, die. Guilt, innocence, etc. have nothing to do with it.

You will never get an answer as to why, at least not in a metaphysical sense. People come up with a lot to stories to make themselves feel better, but there is no why.