Yes, fiber has many benefits. Because it helps food pass through the stomach and the intestines quickly, it helps prevent constipation. Eating foods with fiber also slows the absorption of sugar from the intestines, helping the child feel full longer, and able to concentrate better. That feeling of fullness can also help in weight control especially important for children who are prone to weight problems. To figure out how much fiber your child over 2 years of age needs, simply add their age plus 5 to get the total number of grams he/she should aim for everyday. For example, a 9 year old child would need 14 grams of fiber per day (9 + 5 = 14).

Additional Resources:
http://www.framinghampediatrics.com/Fiber.pdf