Possible hidden twin???

[sally2000]

I just had my 1st u/s at 6 weeks and there seemed to be some confusion as to what a second "blob" was that appeared below and to the right of the baby. I go back for another u/s in 2 weeks. Any thoughts as to whether or not this could be a second baby that's hidden by the first? They were only able to detect a heartbeat with the fully visible baby. Twins run in my fam on my mother's side and dr. thought that might be the case, but couldn't say for sure. Thanks for your help.

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