Here are some older threads you might find helpful:
We don't know for sure if they practiced child sacrifice. The ancient sources we do have aren't totally contemporary and are generally hostile. Even archaeologists have been debating this inconclusively.
Here's one archaeologist's view that supports that Carthaginians didn't practice child sacrifice:
"In ancient times, for every ten children that were born, seven died within the first year and out of the remained three, only one became an adult. Now I ask: is it reasonable that, with such a high level of infant mortality, these people killed their own children?" –Piero Bartoloni
Ten necropolises are the resting places of children. Actually it has been discovered that the greater part of approximately 6,000 children urns found in Carthage, contain bones of fetuses, therefore of still born babies (Phoenicia.org).