Tamera Mowry shared a message about grief after laying her niece to rest with family. The 40-year-old actress attended a memorial service for Alaina Housley, her 18-year-old niece who died in the Thousand Oaks, Calif., shooting last week, on Thursday. "Today we lay you to rest sweet angel. I'll miss you forever and your sweet smile. Until we meet again," she wrote in an Instagram post. Mowry shared a quote about grief from a friend, telling fans she's been clinging to the message during challenging days. "Grief never ends... but it changes. It's a passage, not a place to stay. Grief is not a sign of weakness, nor a lack of faith... It is the price of love," the quote reads. Alaina was one of 12 people killed when Ian David Long, 28, opened fire Nov. 7 at the Borderline Bar and Grill. Mowry remembered Alaina in a post on her son's 6th birthday this week. "Happy 6th birthday Aden! Alaina was excited to come to your birthday party. But as you said buddy, 'She lives in your heart now.' We love you," she wrote. Mowry is parent to Aden and 3-year-old daughter Ariah with her husband, Adam Housley. She and her twin sister, Tia Mowry, came to fame on the ABC\/The WB series "Sister, Sister."