Jada Pinkett Smith has some words of wisdom for Miley Cyrus. The Madagascar 3 star has offered marriage advice to the 19-year-old singer, who accepted her 22-year-old beau Liam Hemsworths marriage proposal last month. The wife of actor Will Smith has suggested that the key to marital bliss is to become friends with your partner. ''Learn how to be friends, especially when you are starting that young. Forever is a long time. When you are starting forever at 19 years old, and it is not to say that there is anything wrong with that, but it is just to know that what it is now and what it will be, it is just going to continue to transform and change,'' she told Us Weekly. ''You have to keep flexibility [in your relationship]. You have to be with someone you consider as a friend,'' she added.