My baby is almost 6 weeks old, has caught a cold (or similar) from his 18 month old sister. Sister was given antibiotics (5 days ago) by GP since her cough was not improving after a few days and he believed she was getting bronchiolitis. Sister is now mostly recovering but baby is getting worse: - screamed for most of an hour trying to feed him 6 hours ago, refused approximately 40 of 100 ml bottle. - has been lethargic most of the day. - refused to shut his mouth to drink his next bottle ( approx 2 hours ago) and took only 30 ml of 100 ml bottle - normal is 130 - 150ml for this one. - has persistent cough (though no whoop thankfully). GP suggested chest clear, cough due to post nasal drip, though lethargy and refusing food are new symptoms.