Take children to age appropriate performances. Children's Theatre performances involve a lot of music, dance, lights and sounds. I would suggest one of their puppet performances when your child is older. Don't ruin everyone's experience by bringing a child who is likely to start crying during the performance!
You COULD, but I wouldn't recommend it. Your child may not remember the play, and may find the bright lights and loud noises very distressing. This also may disturb the other audience members and dampen their experience. Again, it's not against the rules, but I'd not recommend it.
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