You definitely need more detail before any kind of assessment can take place.
What were they playing that was so mischievous? Infants aren't that mischievous? They can barely move. Unless you are writing an animated film, they would need to be older, toddlers at least. Only Damian from the Exorcist was able to kill from the crib.
Disaster strikes? What disaster? Flood? Famine? Plague? In the news there have been reports of toddlers shooting sibling and even parents with found guns, infants are still too weak.
Revelation? If the main characters are infants, they can't talk. How much can they reveal?
I believe that the real story is with the parents or guardians. For example - One parent leaves the kids with the other after a divorce and something bad happens and when the kid winds up in the hospital, the attending parent finds out that they can't give blood because the kid isn't theirs. The infants would just be props to move the story along but this would be more reasonable.
265 week(s) ago