Why does my 6 months old sweat so bad when she is sleeping and she keeps getting a runny nose does this have anything to do with each other ?

Unlikely allergic.: Hay fever/allergi rhinitis/nasal allergies not associated with sweating. Could be a "cold" or the sweats and runny nose not connected. If baby gets sick or symptoms persist beyond 7-10 days, see pediatrician.

Sweating: Could be the result of the baby being ill. We get a chill when our temp is going up with a fever and then get a sweat when the fever breaks. The runny nose could be a sign of a cold that may have low grade fever and sweats. Should get the baby checked if the fever is over 102 or if there is a rash or loss of appetite.