I have a 4-month old baby, whenever she cries, I know immediately that she is hungry. So, I feed her. I noticed sometimes that she is starting to suck on her fingers, I find it adorable watching her doing that. My sister suggested to give her a pacifier. I'm wondering, is okay with her age? What is the appropriate age range? Also, I'm doubting to give her one since it might have an effect on her gums. Will there be?