Hi, my nearly 4 year old I think has conjunctivitis. I noticed yesterday when she woke up she had ‘sleep’ in the corner of her eyes and she said they hurt. This morning and throughout the day she has producing more eye ‘gunk’ and her eye is quite red one side and keeps filming over with more ‘gunk’. Can I get something from over the counter? It’s not bad at the moment and not sure whether there is something preventative to use? Any advice welcomed. Thank you.