I have a 4 month old kitten. She seems to not have gained much weight since I got her. She has only gained one once. I have had her for 3 1/2 weeks. Also her bowel has been very runny. She barely eats anything. She takes a couple of bites in the morning and in the evening. I leave the food out for her during the day, but when I get home it looks like she ate nothing. Should this be a concern for me, or is this normal.