have you lost a parent??

I lost my dad when I was 8 to a heart attach. He was only 32 so it was not expected. I am now 22. I often find myself in random places, like for instance, in the grocery store, I'll see a father with his kids and seriously just lose it. I guess I wonder what it truly is like to have that comfort of a dad. Don't get me wrong I'm not always like that, it just hits randomly. Do you experience this as well?