AIBU to hope for peace?

[TheBouquets]

AIBU to wish that just the odd time my family can get on well together.
I can see a lot of what is causing the problems but don’t know what to do about it all. I get a load of flack all round because of it all. I am the fourth and youngest child (and therefore know nothing at all according to some folks).
The eldest sister has had a lot of trouble in her life various partners several children not all living with her. I remember being quite young and being taken out my bed to go a sort out some of the mess or to be dropped with relatives to sleep over while others were out due to episodes of quite bad stuff. There have been financial disasters which my parents have tried to sort out or help with but there is never any improvement in dealing with money. She only wants her own family with there are problems and ignores us the rest of the time.
The next one is the only boy. Not been much bother to my parents. Always worked, dsil also works p/t. 3 Kids are fine going to school progressing well. Lives about 50 miles away but usual visits about every 4 or 5 weeks. They all go to DM house sometimes stay over the weekend. Have DM over to their house about once a month.
The next one is another sister a single parent. Had a partner but broke up about 1 year ago. She was thought to be doing a bit better than the eldest one and keeping on top of finances, She works but it appear that finances are a bit dodgy. We have suspicions that debt is being run up and not being dealt with. Don’t know if the finances used to be well under control and have recently gone out of control or if I was being fed false information that she was managing. She has one child,
Then there is me. One child, got my own wee flat, work p/t and study p/t.
I know that my DM is very sad which is natural because DF died 18 months ago. There seems to be more to it than grief. I know that (as the baby!!) I am not being told much by DM. I wish she would talk to me.
I know that a lot the family were upset by the conduct of Sister 1 and that it was tried to be covered up and not discussed with older relatives. Excuses were made for her absences from family weddings and Christmas etc. My DM said that she felt she was rejected as not being good enough for sister 1. Sister 1 did a lot of things she should not have done.
Only brother is very quiet. Minds a lot of his own business and gets on with his own family’s life but will not try to help me with all this when I ask. He just wants a quiet life very much like our DF. He is not causing any real worries for out DM and I am glad for that.
Sister 2 is a very stress person. Always does everything fast but not well. She is giving herself extra work which creates more stress for her and those around her. She is constantly shouting at her child and expecting too much from a young child. The child is constantly punished. I don’t think the child is bad but perhaps a bit confused or upset by the barked orders and unrealistic demands.
I try not to cause any stress for DM and eventually myself. I have seen DM crying when she does not think I can see. There have been remarks made by some of the family regarding problems DM has. I don’t like that and even worse I think there are laws against berating a disabled person about their disability and symptoms. It is no wonder DM has problems with all the worry and stress she has had with the Siblings and DM and DF’s health problems.
How can I get people not to pick fights every 5 minutes, and go in huffs which can last years. There should not be all this in-fighting especially when there has been illness death and children involved.
AIBU to hope for some peace and support in this family? I want us to find some way of being a proper family.
A Bouquet!