Editor’s Note: Texas Monthly Presents is a new docuseries airing on Texas PBS stations. Check your local listings or watch full episodes here. Family is powerful. And the second episode of Texas Monthly Presents examines three distinct ways in which a family connection adds dimension and a sense of purpose to our lives.Years ago, contributor Oscar Cásares embarked on a journey along the Rio Grande with photographer Joel Salcido. They took photos and met characters, and Cásares passed all the tales to his daughter through letters and postcards. The journey appeared in the pages of Texas Monthly to highlight life along the border, and today it remains a strong story about family identity.In the episode’s other two segments, taco editor José R. Ralat recounts the…