Hey guys I have a Multi-wire branch circuit that I'm having trouble wrapping my head around. Trouble started when we moved in, wife complained that her hair dryer didn't have the speed it should in the bathroom. 1985 build. MWBCs used in several places in the house. I found that I also experience low power/voltage drop at the outdoor outlet in the back yard. I discovered the breaker that kills the outdoor outlet is the same for the bathroom lights and both bathroom outlets. I started looking for issues in the main bathroom where the lights were also off cause that seemed strange to me. I found that the bathroom outlet had two feeds coming in. One that looks original and was still hot and another that is obviously DIY Daisy chained from the bathroom light switch. I'm guessing there was a reason someone went through the trouble so I'm going to clean it up but leave it in place until I can figure out what the reason was. I suspect that mwbc may be wired improperly and caused issues. The voltage drop (I think) occurred because the outlet was tied into a switch connection via a back stab which is obviously unreliable. The other oddity is that the neutral coming back from the outlet is actually tied to the neutral that seems to be going to the fan instead of the wire bundle it entered the junction with. I can fix the back stab situation no problem but I'm far from a pro. The wire bringing power into the junction is a three wire+ground. The red wire goes to the lights, the black to an outgoing 2 wire. It appears all of the neutrals on the incoming wire are bound together except the one that runs the outlet, which is tied to the neutral leading to the fan which must connect to another circuit somewhere else because it has power. Should I move those neutrals into the pigtail that goes with the incoming hot?