Yes, children should be their parent top priority in life. Children are not asked if they want to be brought in to the world, they just arrive. It is the parents responsibility to take care of the child to the utmost of their abilities. The child's needs should be met and every decision that is made should be made with the best interest of the child in mind.
I think children do become everything for parents. Parents devote their entire lives to making sure that their children are happy. They go to work to support their kids and make sure that their children get a proper education. While they do have other priorities as well, children are their top priorities.