Am I wrong for telling my wife I'm not getting involved with the drama between her and my mom and sister

I know it's a husband's job to always defend his woman. But I find the whole situation ridiculous and I am just finding out what all of this is over. This all started 8 months ago at my sister's baby shower. My wife went and I didn't. They did separate baby showers. The man had their own thing and it was just us playing video games. My wife was at my sister's baby shower. My wife was the one who bought the gifts. It was a swing and pack and play. I guess my sister never personally thanked my wife for the gifts but she thanked our mom. I didn't know that but it upset my wife. They had an argument months ago because my wife felt she was ungrateful. I didn't even know this argument happened. A month after the baby shower, my sister had a stillbirth. We all went to the funeral. It was really sad. I've been trying to be there for her. We found out back in June that my wife is pregnant. We didn't know if we were going to keep it but decided to. I guess my wife went and asked my sister for the baby shower gifts back for our baby. Another thing that I didn't know that happened. My sister left my wife on read. So for a couple months she had been trying to get these gifts back. My sister finally gave them back but they reeked of cigarette smoke. My BIL also went into a depression after they lost the baby and he started smoking again. So my wife got mad. My sister was saying they were hers to begin with because they were a gift. Then my mom got involved and called my wife selfish and that she makes everything about her and this is when my sister reached out to me. I talked to my wife and I finding out now all this drama that had been going on that I didn't know about. She wants me to tell my sister and my mom off but I find this whole thing ridiculous and do not want to get involved with their drama.