Aerial view

Cardamine hirsuta.

Most helpful, thank you!

For once I don't agree with Carol23 - the leaves are the wrong shape and too large (getting the scale from the clover and the lighter). But I do agree it's probably a Brassica.

I don't know either --- maybe this will help
Similar Species: Prickly lettuce can be confused with sowthistles (Sonchus spp.), which have prickly leaf margins but smooth midribs. Tall lettuce (Lactuca canadensis) and tall blue lettuce (Lactuca biennis) look similar to prickly lettuce except they have leaves with smooth edges and midribs without prickles.
Tall blue lettuce (Lactuca biennis), tall wild lettuce (L. canadensis), and prickly lettuce (L. serriola), are the most common types of wild lettuce. All have milky sap.
Bitter lettuce
Willowleaf lettuce

DIplotaxis viminea is similar. What do you all think?

The only two Diplotaxis species expected (but rarely seen) in Texas are D. muralis and D. tenuifolia. Both have leaves that are less deeply cut, and the lobes are more forward, instead of so laterally spread. That said, I worked through the mustards twice and was unable to find anything that fit.

capsella bursa?

Thanks everyone; from all of your suggestions it almost seems as if the plant(s) were a hybrid between dIplotaxis viminea & capsella bursa, yet not quite as the varieties in texas are a bit off as jekeesl pointed out. Also thank you marpa for the wild lettuce information, it will definetly come in handy.

Capsela bursa-pastoris in full. Shepherd's Purse, literally.

Thank you floral_uk! I think I'll make some tea