Research Hypothesis about communication and relationship with family?

Is this a good good research hypothesis:

"There a link between access to communication and healthy relationship with family member(s)"

If not what is the best way to write it out?

"There is a link between communication and a healthy relationship with family member(s)"

or

"Is there a link between communication and a healthy relationship with family member(s)?"

What is more important in a relationship; communication or the physical part and why?