Answered on Mar 20th, 2017 at 7:50 AM
Yes, your father's surviving spouse is entitled to what is called an "elective share". 1/3 of certain assets. The share applies to a variety of assets passing via the will and outside the will. So one should take stock of what she is receiving via non-probate and under the will and decide which option is best for her.
I recommend that you seek out a local attorney for a more in depth discussion of the matter. I do not recommend that you take any action steps without such a consult. Act quickly because by waiting, you may lose certain rights and remedies available to you.