I wanted to add that also I have made efforts to make things more accessible to my children as well. When they were younger I put several already filled cups in the fridge for them to get out when they were thirsty and portioned out snacks in small containers for them to get themselves as well. There is a step stool for the bathroom and kitchen so they can reach the sinks and dishes. Simple things that they could do for themselves, rather than feel like they had to ask for help for everything. While this may not help a child who is overtired and whiny, I think it does help with whining in general.