Here is Jessica, one of the Sweet Valley High twins.  The doll is from the Cool Campus set, made in the 90s.

She stands about 11 1/2 inches tall.

The doll itself seems to be in very good condition.  Her black vinyl parts (hat, vest, but especially the boots) are flaking.  I don't know if the stand is original or custom made by a former owner, but I imagine the latter.

Vintage Sweet Valley High Campus Cool Jessica + Tote Bag 11.5" Doll Stand 90s