I think modeling compassion is the best way to teach compassion. We moms can make more of an effort to be compassionate/sympathetic with others and that will make a huge difference. We may feel compassion, but our children may not be aware unless we make sure to talk about it in their presence. We can also point out when others need compassion and encourage our children with ways to show compassion to that person.
Example: Megan, your little brother is really sad because his friend won’t be able to come over today after all. I think it would really cheer him up if you would spend some special time with him today.