hello and welcome thank you for the query As you said the piercing is old enough to have any fresh infection,its definitely the metal which she is allergic to. Having one s ears pierced can trigger an allergy to metal that makes it suddenly impossible to wear any kind of jewellery or even metal buttons, snaps and zippers. Such allergies are most often caused by exposure to nickel, which is present in quality gold, silver and platinum jewellery as well as in cheaper costume jewellery.Even a minimum quantity of the metal can trigger it. I strongly recommend to follow the steps for treatment of the condition: 1.Avoid earrings till the symptoms subside. 2.Wipe the effected area using a cotton swab/ball with savlon/mild soap( NOT DETTOL !!) thrice a day. 3.apply ointment Flutibact twice a day for 5 days on the effected area,then once a day for other 5 days,and stop application. 4.Avoid the earrings she s been putting just before the onset of these symptoms,as they may be the prime cause for the trigger of the allergic reaction.You can opt for pure Gold/Platinum/or the ones made of stainless steel. Thank You Stay Healthy.