Horace & Tina (2001)

Horace is a short, grumpy, 200-year-old gnome who is the world's greatest mischief maker. His elder sister, Tina, is a 271-year-old incurable romantic who loves to meddle and give advice. Lauren Parker discovers she is the only person who can see Horace and Tina and has to keep their existence a secret from her family and friends without them thinking she's going crazy.