My cat gave birth 5 kittens last saturday. 1 kitten died after birth out of 4 1 one was really premature with only 58 grams. The others were 78 80 and 90. The weak one nursed well reached 100 grams but we lost him today just when we thought he was doing okay. Now my concern is other thriving kitten stopped nursing this morning and when i weighed him this morning he had dropped from 144 to 136 grams. Ever since we noticed it we nursed him with a syringe he dropped to 133 but stayed there. He keeps wandering off from the mum and siblings. He keeps his mouth open and keeps crying. He wont nurse no matter how many times we take him to the nipple. Mom didnt refuse him as she keeps on licking and grooming him. I asked 2 vets they both said they cant give any medication or anything so we should keep feedimg him with a syringe but dont keep our hopes up. What should i do? Why does he keep his mouth open?