If she's a dependable young lady, I say go for it...it's always nice to have a puppy/dog to come home too..When I got my shih tzu, I worked 12 hour days(on 2 off two), she did fine, and got so much love when i did get home..Heck, I just gave my son and his fiance a yorkie puppy and they love him to death..spoil him rotten
I do watch him for them on Tuesdays, as his fiance has nursing school all day, and son is gone for 12 hours, but, the other days, his fiance is never gone for more the 3-4 hours, and little Teddy has his food/water/pee pad and bed in his xpen. But, this little guy brings so much joy to them...There are a lot of them on here that aren't home all day with their yorkies, that work or have school..! You know your daugther, no one else does, if you feel she's responsible, and she really wants one, GO FOR IT!!