Once the Surrogate's Court completes its final orders of distribution and no appeal takes place, the money is yours and you can do with it whatever you wish.
Money tends to make people think differently than they would otherwise. Sure, you're inheriting a large sum of money, but you didn't win the lottery. So you need to consider good financial planning more than you need to worry about whether your wife will get any of it upon separation and divorce. So, my first recommendation is that you contact a good financial planner and determine the best uses for your money in the present time.
Then, if you really want to keep this money separate, contact a local family law attorney, tax attorney and estate counsel in New Jersey.
If kept in a separate account in your name, the $140,00 will remain an exempt asset.
The only sure way to protect the downpayment on the home is to do so through a written post-nuptual agreement. If your marriage were to end in a short period of time after the purchase, and you had no written agreement, you will probably get some consideration for the downpayment in a divorce, but after 5-10 years, it will lose all protection.
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