can use nasoclear drops.

make him smell ajwain potli... it works wonder with small babies... spread eucalyptus oil on his clothes or pillow... it will b easier for him to breathe or use nasal drops

make a garland of garlic cloves or tie some garlic cloves together and put it near baby's pillow while baby is sleeping or you can also put it around baby's neck... garlic helps baby have sound sleep during cold specially with blocked nose...  also keep baby little elevated while sleeping .

ok thankyou arwa

put nasomist drops . also keep ajwain potli it helps with the breathing