Hi BFxyangl
I meant to pick tags for your platform and mod usage. This is vital info for any bug report.
Please try the clean folder approach described here: 📓[GUIDE] Clean User Folder Approach | EA Forums - 12690428
You probably still have them when you put your save back so do you have a backup from before it happened ?
There is an issue where babies can get stuck in the household inventor if you move houses while having a baby but then they usually also show up in the household and shouldn't duplicate like that. I can see how my question was a bit unclear for that. So did you move houses while having a baby in the crib ?