Runt of the litter

My ankle demon chihuahua recently (1 week) had a litter of 7, 6 that lived puppies. The 6th is a runt and smaller than his brothers and sisters. Mom keeps of pushing him away. The wife is having me start bottle feeding him. My question is...being a runt, do you think he'll make it as long as we keep him nourished?

Hello - it depends why he is the runt.  Sometimes a puppy is less strong than the others / less able to compete with the brothers and sisters and gets pushed out.  With the correct attention this one may thrive.  However not infrequently there is something bodily wrong eg they are not sucking properly, and not feeling well, are not strong.   These often have underlying reasons behind them, ranging from palette or heart defects to simple low blood sugar / having got cold.  A better prognosis would be acheived by letting your vet examine the pup - they will at least spot immediately obvious problems and make a plan for going forward.

Please note that it may be vital to have this runt assessed as soon as possible, so ask for emergency triage (the vet to listen to the symptoms and decide how soon the case needs to be seen).