It is so important, as a parent, to note that your children follow your example.
If you are polite, they might say please as a matter of course. If you clear your place, they expect that to be part of dining. If you stay in your seat at the table, they may learn appropriate dining manners. If you brush your teeth and floss, they may learn good dental care. If you are a reader, your child might love books.
If you get frustrated, lose your temper and shout at random people in your house - they might learn to do that. Like I did - this morning.
Shortly afterwards, B got frustrated, started shouting, lost his temper, and kicked his brother (I didn't kick anyone). I set a total shit example and, clearly, my child was watching.
Just imagine this guy shouting in a shrill voice and lashing out at his adoring brother because he didn't want to pull on his underpants without help.
That pretty much sums it up. Don't I feel like the mother of the year.