Sunday is supposed to be a day of rest. Adults understand that. Children, however, do not. Children wake up early 7 days of the week.
It is like children know that their parents went out late. They know they had a good time. They make sure to wake up early on Sunday as punishment. That is the only explanation. Our son was wide awake and ready to go at 6:00 am this morning. For what purpose? He does not work. He did not have any plans scheduled. But he was ready to go screamin at the top of his lungs.
By 10:00 am we accomplished more than most people do on a Sunday. And we had to wait because stores open later on Sundays. Not a concern for our son. And not a day of rest at all for us.