Three years after the tragic death of her mother Whitney Houston, Bobbi Kristina Brown was found face down in a bathtub. The 22-year-old was rushed to the hospital and later placed in a medically induced coma by her doctors, but her health continued to fade. Six months later, Bobbi Kristina passed away from pneumonia.

R&B legend Bobby Brown was devastated at having lost both his ex-wife and his daughter in such a short amount of time, but he's continued to honor their memories throughout the years. Today marks the four year anniversary of Bobbi Kristina's death, and Brown paid tribute by writing an open letter to his little girl. "Hi Baby Girl: Every day I hold you close to my heart," he shared on Instagram. "I think about so many of the things you used to do, from a little girl to a beautiful young lady. I just smile It reminds me of how much I miss my little girl more every day, So loved and so missed."

Brown also announced that he, his family, and his team have launched a charity in his daughter's name. "In keeping the flame burning, our family has started The Bobbi Kristina Serenity House foundation that is doing great things to help others in need, the way you would have if you were here. Krissi, on this special day, we honor you, we love you and we shine a light on your memory."