This is a touchy issue no matter which area of nursing you are in. I work in long term care and have had a family member say "I don't want to hear you have 25 other patients, when I,(notice I) put on my husband'd call light I expect you to drop everything and answer it." This was to the nurse, she did not consider a nursing assistant answering the light.
The management gave us some tools to use: 1) Say: "In order to provide care to all our residents on an equal basis, I needed to finish what I was doing, what can I do for you, now?" 2) Always ask if there is anything else the patient needs? Again focusing on the patient and that we are not here to care for others. 3) If it was too unbearable the manager would step in.
I think that some family members are so fixated or perhaps guilty about this person needing nursing care that that they lash out at the nearest and most visible person "THE NURSE."
Now that I am in management I have given these tools to my staff along with one more, ask "Would you like to speak to Nancy?"
I am not saying this is any magic formula, because I still have family members telling my boss that I was rude, but I am woring on those relationships.
The issue about asking the nurse to change an infant's diaper has me puzzled. I wonder why the family would expect that, unless some other nurse saw the child fussing and offered to help with the child.
The coffee issue again, if the patient is very ill, my staff will offer coffee or to have a meal sent up, but again this is a kindness at usually an end of life issue.
I am not sure if this helps. But ask your management for an In-service on dealing with difficult people.
If you like, I will check my files at work, I think I have something that may help. I will be back with it, if I find it. Good Luck. NA