Dear Brianna, as I already mentioned in another post of yours, learning a new language without the help of L1 literacy might be a good thing for learners in the early stages of their learning process. In this way, in the case mentioned in this post as well as the other one,  they can utilize their L1 Spanish phonological awareness (which, according to researchers, is the major predictor of alphabetic L2 reading ability) without the interference from orthography. I recommand you do a research on the effect of introducing and not introducing Spanish orthographic skills into the learning of L2 English reading. 

Many of my students don't have L1 Spanish phonological awareness because they are kindergartners with no previous schooling in many cases, and they come from families that don't usually engage in literacy practices in the home.

Dear Brianna, phonologcial awareness is not a function of schooling, just think of peope who are illiterate, they can not read, but they have no trouble using and distinguishing the spoken form of the language. My point is, in view of the possible inference effect by previously established letter-phoneme mappings in learners' L1 (Spanish in your case), learning an L2 (English in your case, which shares the same alphabet\orthography with L1 Spanish) without previous L1 literacy experience might be an advantage. In other words, previous L1 literacy experirence might be a disadvantage in L2 learning (the issue, though, is still a controversy). 

Dear Brianna,

There are many ways by which young learners acquire their English. But writers like Cummins (1980) believe that L1 literacy can be very helpful. The claim has greatly been supported through related studies. In fact, L1/L2 transferability is an area which has long been under scrutiny by various researchers.

Best regards,

R. Biria