I agree! Children learn from what they see us doing.
If anything, this was my hardest lesson entering parenting - that I need to put just as much energy into controlling my behavior as I put into the relationship I try to foster with my child.
As you prepare to raise a child, you discover you cannot mold them into something that you aren't already. And if what you want for them is different than what you do for yourself, this is where the truly hard work begins.
I believe Kristina Kuzmic's second husband talks about being a stepfather in her book "Hold on, but don't hold still".
He's basically saying that being a stepfather is so challenging but even more rewarding because when you finally make the children willingly call you dad, you know 100% you've deserved it. You've worked for it, it's not just genetics.