which will is legal?

Generally, the most recent Will is the controlling instrument.  This is assuming that the first Will was properly revoked.  Typically, a person can revoke their will by a later writing (e.g., a new will that is totally inconsistent with a previous will or that statement in the later Will that the intention is to revoke the previous will).  However, if a person does not properly revoke their old Will, it remains alive and it will be admitted to probate along with the new Will.  In that event, the court will try to dispose of the estate pursuant to the terms of both Wills, and if there is an inconsistency between the two, the terms of the most recent Will take precedence.  All the remaining provisions of the old will are still given effect, provided they do not conflict with the new Will. Additionally, in this case, there is a potential further complication here, the second Will was a holographic Will (ie. handwritten).  This can present problems of its own.  Under the Texas Probate Code, a valid handwritten will must be wholly in the handwriting of the testator and signed by him or her.  It does not need to be witnessed and can be written on anything, including stationery.  Typewritten words may not be incorporated into the will.  The wording must reflect a present intent to dispose of property at death. The words, "This is my last will and testament," generally are sufficient to show testamentary intent. If for some reason the above requirements are not met, then it can be thrown out (in part or in whole).  In which case, the first Will will (in whole or in part) becomes the legally operative instrument by which the estate will be distributed. Bottom line, all of the foregoing not withstanding, the second Will should prevail over the first.  

Generally, the most recent Will is the controlling instrument.  This is assuming that the first Will was properly revoked.  Typically, a person can revoke their will by a later writing (e.g., a new will that is totally inconsistent with a previous will or that statement in the later Will that the intention is to revoke the previous will).  However, if a person does not properly revoke their old Will, it remains alive and it will be admitted to probate along with the new Will.  In that event, the court will try to dispose of the estate pursuant to the terms of both Wills, and if there is an inconsistency between the two, the terms of the most recent Will take precedence.  All the remaining provisions of the old will are still given effect, provided they do not conflict with the new Will. Additionally, in this case, there is a potential further complication here, the second Will was a holographic Will (ie. handwritten).  This can present problems of its own.  Under the Texas Probate Code, a valid handwritten will must be wholly in the handwriting of the testator and signed by him or her.  It does not need to be witnessed and can be written on anything, including stationery.  Typewritten words may not be incorporated into the will.  The wording must reflect a present intent to dispose of property at death. The words, "This is my last will and testament," generally are sufficient to show testamentary intent. If for some reason the above requirements are not met, then it can be thrown out (in part or in whole).  In which case, the first Will will (in whole or in part) becomes the legally operative instrument by which the estate will be distributed. Bottom line, all of the foregoing not withstanding, the second Will should prevail over the first.