When I played this game for the first time and came to Auntie Ethel in the grove with Shadowheart in my party, Shadowheart made a remark like "Be careful, something is strange about her".
When my party found Karlach, and I agreed to have her join us, Astarion remarked that Karlach was a killer, and he liked having her with us.
Those companion reactions don't exist anymore in the current version of the game. I read that either patch 5 or patch 6 broke them.
Does someone know of a mod that would bring them back? I searched in the imgame mod manager under 'companions' and 'conversations', but didn't find anything like that.