AITA for bringing up dead relatives feelings during an argument?

For context, my sister, her husband, and I recently got in a fight over her husbands disrespectful behavior towards my mother. At one point things got heated between her husband and I, and i brought up how the behavior started with my dad back when he was in the hospital. My point was to emphasize how it's been a pattern of behavior. I will say though, the way I brought it up was immature, I was reacting to him calling me immature after attempting to let them know of the hurtful behavior. Now they are calling me "soulless", "cruel", etc. because I brought up our father and "she can't get closure". Her husband then proceeded to say it crossed a line and went "below the belt" for bringing up my dad, and my older brother in a past fight. I totally forgot about that fight so I didn't even realize until a few days later what he meant. A while back we had a huge fight with all our family over my sister's behavior towards my parents, and I did bring up how our deceased brother felt the same as I as we had talked about it together before.I do think that was might a been a low blow, but I remember apologizing. So essentially, am ITA to bring up deceased family members feelings, that they told me directly, when arguing about hurtful behaviors?