Create a concept art illustration of an elderly witch in three different poses, depicted in a whimsical, caricature style. The witch should have a spherical body, with exaggerated, rounded features that give her a playful and unique appearance. Her entire form, including her head and limbs, should emphasize the spherical shape, creating a cohesive and quirky design. She should hold a crooked staff and be accompanied by a mystical bird, both designed with elements that complement her rounded, caricatured style. The witch's outfit and accessories should feature rich shades of violet, ranging from deep purples to light lavenders, adding depth and vibrancy. The overall vibe should be lighthearted and magical, with the spherical body, bird, and staff adding to her charming, cartoonish appeal. The background should be minimalistic, allowing her vibrant design to take center stage.