Why We Heed a Friend’s Advice More Than Others'

All of us would agree that accepting advice is generally difficult. But, why is advice a little more acceptable when it comes from one's good friend? I think it is because we trust that our friends, while being external of our problems, would step into our shoes and understand our points of view too, before advising us. And, we probably implicitly believe that they wouldn't get judgemental about us and would certainly count on us when they need help to counter their problems in future. After all, what is friendship but mutual emotional support between two compatible minds?