Not sure thinking about it, because at first you think there are going to be more liberties taken, but then again you are keep money between yourselves so that should motivate a person.
I've seen businesses fail because too much 'I'll do it tomorrow Cuz' but then I've also seen businesses become a sucess because ' If you don't do this work now, I will wriite you out of my will' lol!

I think its down to the work ethos one has instilled in their family, some people just aren't meant to work together, same with friends too.