I had to train several df'd jws and had no problem. My rule was no discussion about the WTS. We were able to find a lot more to talk about.
I've always said hi and wished them well and chatted some and it even wasn't "necessary family business."
A family member was shunned during the time that unbaptized jws were treated like df'd (changed in 1988) and I refused. When the "rule" changed my family had a hard time deciding how they should be treated. I gave him a big hug at the family reunion and then others did.
Even Jesus talked to the Syrian woman and resurrected her daughter.
jws as a group have no love, they strain out the gnat and gulp down the camel.