Oh, I'm so very sorry. My boy Komet will be 27 on 4-26-2021, same age as your Silver, and I've had him since he was a baby too. I had his sire as well, and lost him in 2006 at age 26.
They are such a huge part of our lives - a focus for so many of our hopes and dreams when we and they are young, then so much commitment and work, ups and downs, but always love and joy when they are in their prime, then comfort, peace and even more love (plus some worry) as we care for our beloved companions in their old age. I can't even imagine what our lives would have been like without our horses - easier, but a lot more empty and trivial maybe.
The picture of you saying goodbye to Silver is beautiful. Not a downer at all, though it brought tears to my eyes. Please give Robin some extra scratches and a carrot from me.