Candy is the quintessential instant gratification for a child. Someone who plays with kids and gives them sweets is someone who wants to be liked.
To motivate someone who wants to be liked, it’s best not to be disapproving. Rather than getting mad at your sister, enlist her help.
Tell her how hard it is when the kids get roused before bedtime. Talk to her about the candy before she comes over. “Hey, it’s thoughtful of you to think of the kids and bring them something they like. But sweets make them hyperactive. If you really want to bring something, please make sure it doesn’t have sugar in it.”
Ask if she would help you keep the atmosphere calm when she comes over in the evening. You could let her know that it would be helpful to play tranquil games or read to the kids to quiet them down before getting a good night sleep and sweet dreams. (Better than diabetic nightmares!)
If that doesn’t work, limit her visits to the daytime. You can be honest if you are kind-hearted about it. “You are so much fun that it gets the kids too excited before bedtime. It makes it really difficult for us to get them to bed. So afternoon visits would work better.”
by Alison Poulsen, PhD