I have a number of questions in regards to inheritance
Q. Is a secular will written by an attorney valid according to Halacha?
A. In principle a secular will, by which an individual estate is divided according to his own wishes and does not follow the dictum of the Torah, may not have any Halachic validity, since it takes effect after the death of the bestower.
According to Halacha, dead people have no rights over the property they owned while they were alive.  Therefore, they have no right to dictate what happens to their property after they die. (Shulchan Aruch C.M. 258: 2)
The above greatly differs from secular law which, in principle, recognizes the right that people have to testamentary independence and can do whatever they want with their property after their demise. 
See next question.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a