How did you guys decide that your child was ready for preschool??

I've heard some moms that I really respect say they didn't send their children to preschool at all so I'm curious about that but I really want to do the right thing for Bella and not the right thing for me whether that is send her to get a break for myself or not send her so I can keep her home and with me.
How did you decide? What have you read? Do you know of any good sites or articles about the different school styles?

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