If you are just starting up, you may not know about the new Family Search Pilot Project that has some really great searchable free databses (url below). One of these is the actual images of Texas Death Certificate 1894-1976. Unfortunately, there are very few before the 1920's, as the death record law was loosely enforced. I didn't find (and goodness, I tried!) a death certificate for J.T.
I did double check Billie Penn Pennington's birth certificate. Did you notice that he's born in Wise Co., Texas? You can tell by the county code. I have looked all over Wise Co., and while there are Pennington's there, I can't connect them to J.T. I'm wondering if it's a typo, as Wise co.'s code is 249 and Wood Co's is 250. Curious.
I could trace the Titsworths, though. In 1900, Jessie is with her parents, John Henry and Amanda, in Hopkins Co., TX. In 1910 John and Amanda are in Wood Co., which makes sense, since that's where J.T. and Jessie are married. The Titsworths remain in Wood Co. in 1930. I had trouble finding them in 1920. If you don't have access to these censuses, let me know and I will transcribe.
I did find this death certificate that may be Amanda's. Can't imagine what she was doing in Lockhart (Caldwell Co.), Texas, but she is buried in Mineola, which is Wood Co. May take some more verification. I recommend you look at the original image, since it usually has more info than on the index info:
Name: Mrs. J. H. Titsworth Death date: 09 Jul 1930 Death place: Lockhart, Caldwell, Texas Gender: Female Race or color (on document): W Age at death: 68 years 1 month Estimated birth year: Birthdate: 09 Jun 1862 Birthplace: Texas Marital status: Married Spouse's name: J. H. Titsworth Father's name: Ephraim Brumley Father's birthplace: Mother's name: Sarah Jane Sanders Mother's birthplace: Unk Occupation: Household Residence: Cemetery name: Burial place: Mineola, Texas Burial date: 12 Jul 1930 Additional relatives: Film number: 2135327 Digital GS number: 4163675 Image number: 2102 Reference number: 33023 Collection: Texas Deaths, 1890-1976
Maybe this will help you some. Good luck! Andrea volunteer