Parent-child communication changes drastically over time and so too does the conflict.
With toddlers, parents may use more bargaining: “I will give you two cookies if you eat just one piece of broccoli.”
In adolescence, parent-child communication may include more demand-withdrawl, where a parent can use their power to withhold resources such as the car or an allowance.
As children reach adulthood, relational rules may move from explicit to implicit – “Be sure to call me when you get there,” may evolve to the expectation you will simply keep in touch every once in a while.
Research tells us children seeking and then communicating independence is at the heart of most parent-child conflict across the lifespan. So, a toddler may want to make their own decisions, an adolescent to be in charge of their own time, or an adult to decide what their value and belief system is apart from their parent.