I stumbled upon another case where it seems likely two individuals are in actuality the same man...

There appear to be two men named Basilio de Valdés, both born around the same time. However, the available records strongly suggest that they were the same individual.

Basilio de Valdés of Teocaltiche

Pedro de Valdés and Leonor Tejada married on 2 January 1637 in Teocaltiche. Their known children include:

• Juana de Valdés, b. c1640; confirmed in 1648 in Teocaltiche
• Pedro de Valdés, b. 1641 in Teocaltiche
• Basilio de Valdés, b. c1657; confirmed in 1666 in Teocaltiche; married Catarina de Anda Altamirano
  • Magdalena de Valdés, b. 1676 in Teocaltiche; Española; married José Carrillo, Español, before 1695 in Teocaltiche

Basilio de Valdés and Catarina de Anda Altamirano have one known child, Magdalena Valdés, who married José Carrillo of Teocaltiche.

Basilio de Valdés and Inés Pérez de Ruvalcaba

A Basilio de Valdés also appears later as the husband of Inés Pérez de Ruvalcaba.

Inés was born in 1661 and married her first husband, Juan Gutiérrez, in 1676. She subsequently married Basilio de Valdés, apparently around 1686, after she is widowed.

They had at least six known children:

• Luis Valdés, b. c1686 d. before 1760, Español; married Ana López de Lara in 1705 in Lagos
• Cristóbal Valdés, b. 1689 in Lagos, Español
• Juan de Dios Valdés, b. 1691 in Lagos, Español
• Nicolasa de Valdés, b. c1692, Española
• Inés Valdés, 1696–1735, Española
• Basilio Valdés, b. 1698 in Lagos, Español

At the baptism of their youngest son, Basilio, in 1698, the record states:

“Fue su padrino José Carrillo, español y vecino de Teocaltiche.”

This José Carrillo is the same José Carrillo who married Magdalena de Valdés, daughter of Basilio de Valdés and Catarina de Anda Altamirano.

Basilio de Valdés (b. c. 1657)
├── 1st wife: Catarina de Anda Altamirano
│ └── Magdalena de Valdés (b. 1676)
│ └── married José Carrillo
│
└── 2nd wife: Inés Pérez de Ruvalcaba (b. 1661)
└── Basilio de Valdés (b. 1698)
└── padrino: José Carrillo

In my view, the 1698 baptismal record is particularly important because it provides a concrete connection between José Carrillo and the two family groups.

Then, after the death of José Carrillo, Magdalena Valdés marries a second time on 18 Aug 1707 in Santa María de los Lagos, to Juan Pérez de Ornelas, the younger half-brother of her step-mother, Inés Pérez de Ruvalcaba. 

Yes — this additional marriage makes the case substantially stronger. The 1707 marriage creates another direct connection between the two family groups: Magdalena, daughter of Basilio and Catarina, later marries Juan Pérez de Ornelas, who is the half-brother of Inés Pérez de Ruvalcaba, Basilio's second wife.

Taken together, the matching ages, chronology, locations, marriages and repeated family connections make it highly likely that the two Basilio de Valdés were the same man. The evidence points to one Basilio who married first Catarina de Anda Altamirano and later Inés Pérez de Ruvalcaba, with the two families remaining closely connected throughout the following decades.