How do you stop a 3 year old from constantly getting up in the middle of the night?

Since 4 or 5 months ago, my daughter started getting up at least twice a night and calls down to our bedroom for my husband to fix her bed or get a drink of water. She has always slept realy well since she was an infant so I am not sure how to handle her nightly wake-ups. We have tried explaining how important sleep is to everyone. We have also tried explaining that if she gets up she can do all the things that she wants us to do herself. Any advice? Thanks!