Baby A healthy, Baby B not so much

Went in for an u/s today. Baby B's gestational sac contained a yolk and not much else. 💔 While I am saddened by the loss, I am so happy Baby A is doing well. Measured 1 day behind but RE was not worried, stating measurements aren't perfect and can vary based on angle or the baby's position... only when they are a week behind is there a cause for concern. We actually heard the heartbeat today at a 136bmp. 💓 The loss of Baby B is sad but I still have a life growing inside of me and there is much to celebrate. I've been a little down today but I can't let it sully this experience either. I'm feeling conflicted, but honestly more positive than negative. I would've loved to have a healthy set of twins, but I still have so so so much to look forward to with a singleton. 💜