I would still probably just use earplugs instead.

If you say she uses your phone a lot for pictures/videos/facetime, don’t get the SE. The camera and screen are just not worth it.

I’m not super familiar with the A12 but it looks like it uses USB-C and I’m assuming she has a number of those cables lying around. In that case, I would recommend the 15 at minimum.

If that’s too much, you may want to specify a firm budget for recommendations.