“Happy Birthday Mile !!! Hope it's the best one ever !” he declared in the post’s caption. “(I know I dropped the ‘y’. That’s what I called [Miley Cyrus] most of her life.) ...

Related: All About Miley Cyrus' Famous Parents, Dad Billy Ray and Mom Tish “Happy Birthday Mile !!! Hope it’s the best one ever!” he captioned the post, adding, “I know I dropped the ‘y.’ ...