Not Their Fault
Make sure to emphasize to the child that none of this is their fault. Remind them that being bullied is not a sign of weakness on their part, and that the bully must be dealing with their own problems and are choosing to take it out on others.
Encouragement
A great way to encourage a child in this instance is to aid your child in building resilience. Body language and voice tone can help immensely against bullies. A lot of bullies are looking for a reaction, so if you can help your child avoid this, it can help a great deal.