I've been following this thread for almost a week now. I found it when I was looking for tips on how to try to make a 19F as I wasn't having any luck. Sadly, the one female I had to attempt it was too old by the time I found this thread. That just gave me an excuse to start a second tribe though. Anyway, here are some additions for your research.

First Tribe:



3 M + 19 F = 21 F
No grandparents. This couple also produced a 6 F, but I didn't get a screenshot.



30 M + 27 F = 10 F

30M no parents -- 27 F parents 30 M + *23 F/Grandparents 30 M + 19 F=*



12 M + 27 F = 4 M (Same 27 F as above.)

12 M parents 5 M + 17 F -- 27 F parents - see above
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Second Tribe



2 M + 13 F = 21 F

No grandparents



9 M + 29 F = 2 M

9M parents 2M + 19 F --29 F no parents
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I added grandparent info just incase. I hope this helps you figure it out!