Brushes make a HUGE difference in your child's ability to paint successfully and without frustration. With that said, Fibo recommends that your purchase a small, medium and large size brush, with a short handle, and an angle or flat tip.
Why multiple sizes? Because it's hard to paint a picture with 1 brush that may be too big or too small!
Why short handle? Because it's easier for children to hold. Tip: watercolor brushes are typically short-handled and acrylic/oil brushes are usually long-handled.
Why angle/flat tip? Because mop/round brushes offer little control and hard for kids to achieve straight lines and details.