Funny the main reason I did it this way is because a sibling asked to move with me with her 2 children because she knew I had the space.

In addition to that house, I'm also trying to push my siblings with my Mom's house to get that rented at least (she passed in June 2012), but it needs renovation. 

My dad and his siblings all have horrible relationships as a result.

It is important what you put in the lease of course, but the most important thing is to have one and go over the details of it before moving in.You have  family with many younger siblings, one of the things you are going to need to deal with is the other family members treating this like her home. 

I heard all the tenant stories and went with her to view potential acquisitions.Oddly, neither of my siblings own investment property. 

Like a parent, grandparent, or sibling. 

I found BP through my siblings, one is a REA and the other is also learning REI.

Parents or siblings with kids that you trust to watch your children from time to time?

I'm probably always going to remember that deal, and that guy's name who was doing whatever it took to take care of his mom while his siblings slacked off.

You can, however, invest your SDRP in a sibling's business, uncle / aunt, niece / nephew, cousin, etc.Your accountant or attorney should be able to answer your questions.