Here are some quick hints to make your pictures perfect.
Make sure to have an engagement picture session. This will allow you to get to know your photographer. More importantly, for your photographer to know you. We like to know if you are sensitive to light, blink a lot, have a favorite side or a favorite smile. Your photographer could get some background information on your family members if there is some tension between family.
When taking group shots remember to focus on the photographer. Contrary to popular belief, the adults are usually the ones not looking at the camera because they are trying to get the kids to do something. Children will do what they do. If the adults are not worried and looking ahead, it is easier to get that perfect picture when the munchkins do look up and smile.