There's generally no good reason in Texas or elsewhere why you can't have both a traditional testamentary will and a living trust at the same time. Both of these legal instruments specify what should be done with certain assets upon the owner's death. Living trusts are similar to wills in that respect but the assets are conveyed to the control of the trust during life. In the case of the will, the assets are not transferred until after death and probate of the will.
The living trust does provide some distinct advantages that are worth considering, according to one certified public accountant who is also the president of the National Association of Estate Planners and Councils. For example, the estate at death can be administered more quickly because the living trust assets do not go through probate. This allows for probate assets to be eliminated or minimized. The decedent's estate may be opened and closed in rapid order with no waiting, supervision by the court, or ruminating about what is the status of the estate.
Additionally, certain death taxes may also be properly avoided by using the living trust during life. At any time that assets are needed, they can be withdrawn from the 'revocable' living trust. Assets may be distributed through the living trust and they may follow your instructions on how often and what amount should be distributed. There will be situations, however, where some assets may be in your name at death.
In those cases, the asset must be probated pursuant to the will. If the amount is not much, they can probably be processed through an abbreviated procedure for small estates with small assets, usually just $15,000 or $20,000. Finally, despite the seeming simplicity of the concepts described above, including living trusts, there is sufficient complexity and variations in procedure in Texas and elsewhere that make it highly advisable to consult with an estate planning attorney or other qualified professional prior to taking action.
Source: Time, "Why This Estate Planning Tool Beats Just Having a Will", Kerri Anne Renzulli, Oct. 6, 2014