Expressing Emotions

My father has early onset alzheimers.  I have 3 siblings and we are working together in amazing ways to figure out next steps.

But, as you would expect, we aren't always in agreement.  And we don't know how to express disagreement.

I've been feeling emotional about all of this lately and sense it from everyone.  I feel strongly about certain things and don't know the best way to communicate them.  Email and talking on the phone aren't working any more.  It would be great if we could clear the air.  Ideally, a third party facilitator would be best.  Does anyone have any suggestions along these lines?