The Enchanted Attic by M.D. Spenser

DO MICE MAKE MUSIC? Nicole and her sister, Casey, move into an old house. Nicole things the nighttime noises she hears are nothing more than the scurrying of mice. Then she starts to hear eerie music coming through her ceiling. She realizes with a cold, clammy shiver that something far more terrifying than mice must be in the house. ... And it is up to her to find out what it is, BEFORE IT'S TOO LATE!!