Sweet Ways To Say Happy Birthday To Your Best Friend (Bestie). If your best friend is celebrating another year of life, make sure to remind them just how much they mean to you by wishing them a heartfelt “happy birthday!” Whether via text, phone call, or even in person– every little gesture will let them know how important they are. Get creative this year by sending a sweet message or performing an act of kindness that your BFF would appreciate—here we provide some heartfelt ideas to help…