Hi ladies...Got a bfp 2 week ago at my yearly. Mt dr had me come back in today for a sonogram. There were two sacs, one measuring 5w5d with a yolk and one *i think* measuring 4w6d, no yolk. My dr seemed pretty confident that that sac will remain empty, but from the research I've been doing today it seems common to have one running behind. Though I don't know ho behind is too behind. Any one with similar experiences???