Bloomberg.com is reporting on VERY messy battle on a probate involving a Texas oilman's estate. http://www.bloomberg.com/apps/news?pid=20601103&sid=auPHfoPfzSHA
The gist of the fight revolves around whether the deceased was manipulated into giving to charity, instead of his kids. Perhaps tellingly, only one child is arguing that the deceased was manipulated.
There are some things you can do to lessen the impact of later fights about your will. No-contest clauses and self-proving affidavits help. Also, if a messy probate court battle seems likely, a living trust (as much as I might disparage them in other contexts) may be a good idea. If a family fight sounds less than theoretical in your situation, contact a licensed attorney who can assist you in creating an estate plan that can limit or prevent those fights.