That's great news to read this morning. It's heartwarming to see you post in a positive way, and I can almost picture you looking somewhat relieved and optomistic. Hopefully Puddy will continue to improve - poor girl has been thru sooo much! As has Mom!!
I don't mean to sound disrespectful with what I'm about to say - but why hasn't your vet been able to see the whole picture of what's going on with Puddy?? You'd think with the tongue/mouth issue would have been a clue in regard to the B12 - and it appears to be working for her. Maybe he was too focused on one problem and completely missed another?
Whatever - I'm just glad someone found this info for you and that it appears to be helping. Still keeping fingers, toes, and poochie paws crossed in hopes that Puddy continues to improve!!