Then Shall They Fast

Years ago, a loved one died, and I was led to wonder if it might have been my fault. 

I had unintentionally left my phone on silent for several hours, and discovered that during this time it had amassed an atypical number of missed calls. The first voicemail gave the reason for the urgent volume: a family member had suffered a sudden and severe medical emergency, and I was being desperately contacted in hope that my prayer could be added to those already pleading for divine healing. In what was hours for those experiencing the crisis, but a matter of seconds for me, I reached the last message; the urgency in the voice of the caller had been replaced with resignation and devastation. It was too late. The person had died. 

Would it have made a difference if I had been able to join the prayer vigil, and add my voice to the tally of concerned believers in Christ pleading for that life to be saved?