Portrait of a Young Girl. Adriaen van der Linde.
Posted because I'm curious what the object is she's holding in her right hand. It might be a toy of some kind, but it appears to be tied around her waist.
Addendum: Reader xcentric came up with the identity of the item in her hand. It's a baby rattle/teething toy which is thoroughly explained at the link (a post I wrote (!) for Neatorama last year.)
Image found at Marinni, via Uncertain Times.