My Arabian, Ariel, is out of a rescued mare. Ariel was to be put down, shortly after her birth, due to some health issues (from the malnourished mare) so I 'adopted' her . Straight away then, at six weeks old, to MSU Large Animal Hospital. Went real slow with her for four years, to give her the time she needed to overcome her medical issues. Today, she is ten years old, she can do all the things they said she never would be able to do! She is a miracle. She had a strong will to live, which is what I responded to. The name, Ariel, means Lioness of God.
My Ariel looks a lot like yours, on the left in your photo, complete with 3 white socks.