It is definitely common for family members to act this way. I think most are so entrenched/attached that it may not be possible for them to even consider that their religion is not the one and only true religion.
I am going through a situation with my family now that will surely result in an elder(s) call, even though I haven't been to a meeting in over two years. I mentioned some doubts I had and the research I had been doing to my brother and his wife. She promptly told my folks and the wildfire of gossip has spread to the extent that I have heard that I am an apostate, my wife is dragging me away (she has no interest either way), that my brother's exwife in another town is responsible, That I am having an affair and am splitting up with my wife, and on and on. My wife thinks it's funny, but I am not real happy about it. I have chosen to keep waiting until someone decides to confront me, whether that is my family or the elders. I plan to be kind, but honest when that happens. I have no problem with anyone who stays in the Org, but it is just not for me.
I think that if one displays the true christian spirit of love and forgiveness that Christ displayed, that it is the only chance one has of helping these people understand because that spirit is not promoted by the organization. The WTB wants to control and manipulate.