You sister knows you like no one else. When you have something exciting to share, she is the one you want to tell first. She is your best friend and you share everything with her. Now its time to share a warm cup of coffee with these Sister Customizable Coffee Mugs. Our Personalized Mugs are Dishwasher safe & include FREE Personalization! Personalize your Sisters Coffee Cup with up to 4 Sisters names. Mugs are available in different sizes ranging from 11 ounces to 20 ounces.