I've been looking around to see what I can figure out, what reason there may be for her missing so many. The typical 'what did I do wrong during pregnancy'...

The dentist asked about family history. Ex BIL (18) supposedly was told something similar years ago, but they didn't look any further into it. A cousin of mine also mentioned that 4 of hers didn't exist, but from my reading, anything under 5 is relatively normal. If her top teeth on the right hadn't moved so much, & the others looked like they were coming in I probably wouldn't worry so much. Her 2 bottom eye teeth & the top left eye tooth were lost about 2 years ago & still haven't come in. The top one seems to have broken through, it's just taking it's time. The bottom 2 might just be extremely slow?

I've read that it could be a sign of so many different syndromes, I have no idea where to start there, so I haven't, or if that's exaggerating & it's just a fluke. Neither dentist has said anything, but the first one wasn't very helpful at all.