<s>[INST] My son has been running a fever of about 100.4 since yesterday afternoon. He's about to get two top teeth in so i'm thinking it might be from teething. However, i just noticed a foul smell coming from what i think is his nose. He has had a runny nose, and earlier when he sneezed it was a tiny bit green. He's nine months old...Was wondering could it just be teething or something more serious? [/INST] The greenish secretion is mostly due to bacterial infection in the sinuses that will need mucolytic and if there is fever or enlarged lymph node , he will need antibiotic  for 7-10 days the teething may only lead to low grade fever, but it also leads to low immunity so he will be more liable to viral or bacterial infection be careful for his hygiene and avoid close contact with any infected persons </s>