Weight not mentioned. If on breastfeeding they don't fall ill. It may be gurgling sound from the chest (gher gher), that is normal. Sneezing is also normal. Runny nose and cough is there then better to consult. No bottle feeding. If any of family members is having cold then they should avoid contact, follow hand washing. And if mother has viral, then she should wear mask while breastfeeding. Still having doubts, then better take a consult.