Keep us posted on this, you will certainly be in our thoughts. I do know parents that have had this occur, but it was usually for a reason. Let us know if you get an update, we are here for you.
I'm sorry to hear of your loss. I had a vanishing twin and found comfort in the thought that my daughter will always have a special angel looking out for her.
Just remember that the baby you lost is in Heaven and God needed it with him. You are its mother and always will be. Your baby is just in Heaven. It will look after you just like you looked after it the first 7 weeks of its life. It is in a much better place and is very happy. This is what my priest told me after I miscarried my first baby. It really did help. I still mourn that child but know I will meet it again in Heaven someday. I did know someone that lost a twin and the other is happy and healthy. Good luck and sorry for your loss.
I had a vanishing twin, and it is indeed very common. That doesn't make it less sad and disappointing. The day you're told, it is like being at a birthday party and a funeral in the same room. The baby that is still growing will probably progress and be a totally normal pregnancy, that is the usual outcome if the twins are fraternal. I might note, for a while you might still be able to see the second embryo, as a dot on ultrasounds, as you are getting them during the pregnancy. It is sort of bittersweet.
Vanishing twins are VERY COMMON. I personally know 2 people that this happened to & have gone on to have a healthy child. My Prayers are with you.
I am so sorry. I am glad to hear baby a is doing so well, but my heart hurts for you and the loss of baby b.
I am so sorry :( I will keep you and Baby A in my prayers (((hug)))