If it is...how does it work if I live in Seattle and dad lives in Everett...?
Family Law Attorney
Like many states there is a preference for the child to spend as much time with each parent as possible, but because of traveling distances it's not always possible. It also depends on whether the children are school age.
If they aren't old enough for school, you could have the children one week with you, one week with the other parent.
If they are school age, someone will have to provide transportation to and from school during their time, not to mention transportation for any after-school activities. If you and the other parent don't get along well, then that makes things much more difficult.
The shared residential schedule (which is what we call "joint custody" in WA) doesn't necessarily work in every case. Below is a link to the law governing parenting plans.