As parents or educators, dealing with ‘difficult’ subjects is always a challenge. Video is an excellent tool in your armoury and animation is perhaps the most child-friendly medium to use.
if you are looking for a good resource of child friendly animations, you could take a look at www.brainpop.com.

Set up over ten years ago by Dr. Avraham Kadar, M.D., an immunologist and pediatrician, as a creative way to explain difficult concepts to his young patients. Ideal for both group and one-on-one settings, BrainPOP is used in numerous ways, from introducing a new lesson or topic to illustrating complex subject matter.
Most of the subjects are discussed by the animated presenters Tim and Moby (the robot) and the subjects are many and varied.
With simple diagrams and very plain speaking the approach is suitable for a wide age range although I noted that Brainpop has also introduced a Brainpop Jr Site.
Sadly, it is not a free site but there are a range of subscription prices to suit whether you are subscribing as an organisation, family, individual, school etc.
Visit the site at: http://www.brainpop.com