Spare the rod, spoil the child. There is nothing wrong with disciplining him or her in a loving manner. Many of my friends told me that I was too strict with my toddlers (stopping/ scolding them for misbehaving) and should just let kids be kids while they were all running around. By the time my number a few years older, they were also the only kids that consistently obey their parents.
If they are too old for this, and you know you’re going to have a problem getting your son out of bed in the morning, start the night before. Explain what the consequences will be if they cannot do when we get up, and then follow through with it. This way they’ve made the decision knowing what will happen.