I’m fostering 3 kittens and their mom. Two of the kittens express absolutely no interest in eating any kind of food. I’ve tried 2 different soft foods in variations of warm KMR or water. I’ve softened up kibble. Tried various dishes. I’ve been trying all of this since they were 4 and a half weeks old. Mom isn’t feeding nearly as much these days and is scheduled for her spay surgery next week. Not much weight gain happening but they’re not underweight. Any tips?