Frankly, I think
Mildred is usable because things like
George and
Henry and
Charles are usable again. So go for it!
Millie is at least, a very easy nickname if little
Mildred is not fond of the reactions she gets - because I think people *would* comment often on how unusual it is.
Three boys nappin', one mama namenerdin'
To peruse my top 100ish names:
http://www.behindthename.com/pnl/82589
He is becoming greater, I am becoming less
Bits of the journey here:
http://jodifriesen.blogspot.ca/And some family cuteness here:
https://www.flickr.com/photos/41705228@N08/