"She was supposed to buy ya shorty Tyco with ya money
She went to the doctor got lipo with ya money
She walkin' around lookin' like Michael with ya money
Shoulda' got that insured, GEICO for ya moneeey(your money)
If you ain't no punk holla' we want pre-nup
WE WANT PRE-NUP!, yeah
It's something that you need to have
'Cause when she leave yo' ass she gon' leave with half
18 years, 18 years
And on her 18th birthday, he found out it wasn't his?"
What up Kanye, I'mma let you finish...as soon I do a quick legal analysis.
You've got people in the club hollering they want pre-nups. Is it something that you need to have? Is it going to prevent her from "leaving with half?" You seem to have two issues: 1) You don't want to pay child support and 2) You don't want your spouse walking off with your assets.
California is a community property state. This means that any property acquired during marriage is presumptively property of both spouses. This includes salary and wages earned by either spouse. Is that what you meant when you said she's going to leave with half? You're right, in CA, she gets to leave with her half of what you earned just as you get to leave with half of what she earned. This is the default rule.
You can contract around the default rule with a pre-marital or pre-nuptial agreement. You can agree to just about anything in a pre-nuptial agreement. For example, you can agree that each party's salary and wages will remain separate property. You can also limit spousal support or have your spouse waive it entirely. The sky's limit! Or is it??
You cannot limit either party's contribution to furnish child support, which leads us to our first issue.
Child support obligations
Sorry Kanye, she is going to walk around looking like Michael with your money whether or not you have a pre-nup. You can't contract around child support.
But what if it wasn't yours? Well, any child born to a married couple is presumed to be the biological child of that couple. A married man may bring a suit to establish paternity, but the window on this is narrow. After two years, you can no longer initiate a paternity suit. I guess it doesn't matter in this scenario anyway, because your spouse isn't going to tell you until he turns 18.
Right to half the assets
This is a right that you can contract around. You can both agree that your respective salaries will remain separate property. You can both waive the right to spousal support.
However, you still have to be careful! You can't foist a piece of paper and expect your lady friend to sign on the dotted line. The agreement will be invalid if she was not represented by independent counsel and given at least 7 days to sign OR she was not fully informed of all the terms in the writing (she'll have to sign a separate document acknowledging this) and given at least 7 days to sign.
Additionally, the court can later decide that the waiver of spousal support is unenforceable. If the agreement, at the time of enforcement (not the time that it was made), was so unfair that to enforce it would be unconscionable, the court will not give it any effect. You may still have to pay child support after paying fancy lawyers for drawing up a pre-nup due to changed circumstances.
Pre-nup, is it a good thing to have? Sure.
Is it going to solve that mess you've described? Only half. ;)