Could this be a pair of Painted Buntings (Passerina ciris)? They have relatively narrow bills and the bills are light in color. The bills on the birds shown seem a little think and short for a Rufous-backed Robin, but are right for a Painted Bunting. The bird on the left has the red chest and belly, and the blue head of a male Painted Bunting (I can't see if the back is green), and the bird on the right is a uniform yellowish-green like a female Painted Bunting. This is a common bird in Mexico, Texas, and Oklahoma, with a large portion of the population wintering in Mexico.
@carlos55 Thank you! I'm glad to hear that they're breeding them! They are common in the summer where I live (Oklahoma) but they migrate to Mexico in late September so I don't see them for half of the year. My understanding is that the males retail their colorful plumage year-round, unlike male Indigo Buntings that molt into a brown winter plumage (or plumage with brown tips).
