I'm trying to get started with my business idea, but I'm looking for at least one partner. I've found one, who I know vaguely, but he wants his brother in too.
Although both seem competent enough, I'm a bit reluctant to work in a three way split scenario with two relatives possibly teaming up against me. It is a worst case scenario of course, goal is to get the business running, not to fight.
How do you feel about such a scenario?
The only thing worse than a friend for a partner is a relative. I was warned against it and ignored the advice. I paid dearly. I would never do it again.
You should be evaluating each partner on their own merits. It's great if your partner can find you another who is worthy, but you should determine on your own whether or not you want the third wheel.
This should also be a warning to you about working with this partner. You have not yet committed to him, and he's making possibly unreasonable demands of the business.
In regard to control, you don't have to split the company equally between the partners. It's your company alone initially, and then you make an offer to the partner. You can offer 10%. Or 50%. Or 90%. It's up to you to make the offer, and up to your potential partner to decide whether or not to accept it.
I have had personal experience with this. In fact, continue to do so as my own relative is currently 'dead wood' in a startup I am trying to launch.
My advice on this would be simply don't do it. It helps not having your own relatives in so you do not lose a relationship and it also helps avoid any nasty situation where a relationship between the other partners does not backfire onto you. The existence of a familial relationship tends to sometimes also portray the wrong impression - that complacency is ok, which it is NOT in a startup serious about succeeding.
I was warned about the issues that arise when you do business with family and friends early on as well. I wrote a pretty detailed blog post about this that covers 5 major concerns that you should take into account when doing business with friends or family:
To read more about each point please go to 5 Steps to Follow When Doing Business with Family or Friends.
The fact that you are not comfortable right now and you are asking for advice should be enough reason for you not to do this. Follow your gut.