My father and I are lefthanded, my sibling and mother are righthand, we all eat with the fork in our left hands.
If I'm carving a joint of meat or cutting a crusty loaf, I'll hold the knife in my left hand.
I guess that having parents of both left and right hand dominance, I learnt to do many things both ways and have stuck with whichever way seems easier for me for individual tasks.
When I was teaching my own children, both right-handed, to do certain tasks that I do with my left hand, I found the easiest way to do things was to sit opposite them and they could easily follow what I was doing but the other way around and using their right hands.