That is terrible news. My family prayers are with you. To be so high and then have a death is hard to understand.
Not too similar a story but I had to put one of my old females(BigBig) down. Her last babies are still with me. Everytime I look at them I see their mother. A few of her daughters are now as big as she was. It's a Good/sad memory.
I wish you the best with your little ones.