"Historically you and your DD are both Mrs and only school room girls are Miss. (18th c. and earlier)
But the fashion for Frenchness in the 19th c. saw Mrs get taken away from all high status women and limited to only married women. With rare exceptions, ie a housekeeper would have the courtesy title of Mrs.
1901 saw Ms. and Ms. literally means the same as Mrs did before the Victorian French worshipping nonsense."
@Onnabugeisha - thank you; that was information I didn't know.
What I meant when I said "in a historical sense" was that I don't consider myself the virginial young girl because I have children. I was 20 when I had my oldest and, even then, it was something I felt very strongly about - I always disliked being described as "Miss [insert name here]" though. But I wasn't married, either, and felt too young to be labelled "Mrs" at the time (tell that to my children's schools/doctors/so forth, however... they presume I'm married!) so went for "Ms" instead. As it happens, I'd much rather use no title/label whatsoever, but that's a gripe for another day. Technically, like a previous poster, I'm entitled to call myself "Dr" or even "Professor" on my forms... but I don't. Maybe I ought to. But the decision to use the title "Ms", back then, for me was one that a lot of people couldn't quite wrap their heads around - so I used the above mentioned way of explaining to them why I'd made that choice. I'll answer to "Mrs [last name]" if I'm addressed by it now, because I'm old enough that people simply assume I'm married (which they shouldn't... but they do). But when my oldest was born? Nope.
My 26 year old daughter, however, is very firmly a "Miss" and, when she marries, is determined to become "Mrs [his last name]". That's her choice, and ones she's made very happily for herself. I find it a little amusing, though, because she doesn't bear her father's last name. Or even my father's last name. My children carry my mother's grandmother's maiden name, because I - again, as a 20 year old, just out of an abusive relationship - refused point blank to follow patriarchal rules about naming my precious infant daughter, and went for the name of a woman whom I remember as having been very staunch in her beliefs concerning women and our rights. Then again, her mother (my 2xgreat-grandmother) was something of a (rural) suffragette and those beliefs have trickled on down through the generations... to my own daughter, who is happy to (and has the right to!) rescind them! 
But the point stands that until I needed to start filling out forms for admissions or applications regarding my children, I didn't need to tick any boxes concerning them. I actually didn't tick "Miss" for my daughter's forms as a baby - left them blank, as I did for my son. Other people decided they were "Miss" and "Master". Society is, as it is, and it does like us all to be in neat little labelled boxes for some reason or another... Legally, though, I will never be a "Mrs" - because I will never marry. I'm content to be a "Ms", with a "Miss" and a "Lord" for (adult) children.
Each to their own.