No idea what this little bird is

I thought it was a kinglet when I was photographing it, but the yellow on its head tells me its not a ruby-crowned and yet it doesn't have the black marking on either side to make it a golden-crowned. What is it?

Pic 2 of 3.

Last one.

I think it's one of your Texas-specialty vireos... couldn't say which from the photos.

First pic looks a bit like White-eyed Vireo, but the next two don't show this - could they be different bird(s)?

Resin

Yes, they could easily be different birds. After altagardener posted, I wondered if the first one was a White-eyed Vireo too.

My first thought was an empidonax, but they can be real difficult to separate in the field. Perhaps a Yellow-bellied Flycatcher.