Just had our first ultrasound and happy to report we have a very healthy baby measuring right on schedule (Due date Aug 1) and healthy 170 bpm heart rate. We were also surprised to find out there was a twin who appears to have stopped developing at 5 weeks. It looked like a smaller empty sac or a small yolk sac in it but no baby or heartbeat. They want to recheck in 4 weeks but said there should be no concerns with healthy baby.

Anyone else had this?

Pic below... the last one shows the small black sac upper left which is the vanishing twin.