Children 2 and under do not need a ticket...but common sense on weather they should be there should be used.
Yes, they can for most concerts. When purchasing tickets, it will state on there if no children can attend or from what age. Also, I just went to one and there was a family of 4 with 2 kids under 9 years old. It was too loud for them and they could barely see the stage and parents were lifting them up, eventually the kids past out on the seats and parents continued to watch the show. Get tickets on a slant.
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