go into a sephora store & look at all of the sets & their brushes. i liked the slim essential brush set because each brush was clearly labelled on its handle & the collection was stored in a classic black zip-up bag. the only thing missing from the "se" set was an eyebrow brush, which i purchased separately. there were other sets which were pricier & still other sets seemingly be marketed towards preteens.

No, these are not treated with a anti-bacterial agent. Sephora notes when its brushes are treated. They used to have a set that was for $69 and some of the platinum collection brushes are (the synthetic ones).

Yes.

Slim Essential Brush Set , she will love it, soft bristles and non-irritating.

Brushes are full size just like what you would get al a carte in the store. The width is a little smaller than the width of my hand when closed (4 inches maybe) and its about 8 inches long.

You could use it in a pinch, but a kabuki brush works better.

Th bruses are full size, but the handles are smaller.

Large brush is for all over finishing powder or bronzer. Angled bristled brush (second from left in photo) is for contoured application of blush, bronzer, or illuminating powder. I prefer a normal blush brush that's rounded (no angle). Middle brush is a large eye shadow brush for all over color. Smaller brush is for eyes, but for more detailed application such as highlighter under your brows. Far right brush is a retractable lip brush to use for applying gloss, lipstick, etc. It's excellent to use this sort of brush to line your lips using the pigment from a lip stick tube and then apply the lip stick per usual. You'll get a clean line.
This kit does not include any foundation or concealer brushes, which is what I think you want. If you use mineral or powder foundation, then you will want a large powder brush (like the one in this kit) and a large kabuki brush (very short handled brush with lots and lots of bristles for great blendability and coverage control). If you wear liquid foundation, then you want to use a large foundation brush which is flat and stiffer than a powder brush. Also buy the smaller version (sometimes called a concealer brush) so that you can apply concealer or your liquid foundation around eyes and nostrels.

Brushes are a microfiber, but "very, very" soft and they make applying all the different makeup a pleasure!!

The material of the brushes is microfiber. I don't know if that comes from animals, but hope it helps!