No baby in sac!

Hi! Quick question (This is not about me I am not pregnant and I already have two boys of my own) My “Friend” is 8 weeks pregnant and a few days ago she went for a ultrasound. Now during that ultrasound she told me that the nurse said they DID NOT! See a baby in the sac or anywhere for that matter.. I’ve experienced this myself (only ONCE) and had a miscarriage maybe a week after I saw the ultrasound. I told her that but she believes there’s something in there even when she saw nothing already and she’s still trying to pick baby names.. I’m not trying to be mean because I know it hurts to have a miscarriage. But I feel like she needs to stop holding onto something that’s not there. She can always try again. But my question is, She believes they did it too early that’s why they couldn’t see a baby. Do you think that’s the case?