I remember reading a children's chapter book back in the early 70's about a girl visiting the ruins of an old house (can't remember if it was still standing or not) and being watched by seven ravens or blackbirds. It turns out that the seven ravens are witches. The next thing I recall is that the girl unknowingly finds herself in the past and being invited into the house by a kind lady who lives there. It turns out that she has seven daughters. I remember the girl asking to use the phone to call her family to let them know she's ok, but of course they don't have one. Also, I remember the lady insisting that she stay the night because it was getting dark and the snow was getting bad.
Does this sound familiar to anyone?