Shalom1:
I read your last post with a such heavy heart for you. All I can suggest is to slow down and breathe, collect your thoughts and get organized even to the point of using a lined pad to itemize WHERE you have looked.
Identify each room of the house and go through itclockwise, purses, pockets, diaper bag, file folders, brief cases, laptop case, behind-under-in furniture...check off on the list. Outside the house. What offices might you have taken the passport to? Car, work, bank (safety deposit box, manager's office), lawyer, friends, etc and go through each of those places the same way you did the rooms of the house. Do you have a special place you keep your own passports? Was there a time when you had to remove your baby's from that location, say to fill out information for VO or medical? Could it have been left where you DID the medical?
It will be found. All the best.