E! caught up with the “Motivation” singer at the Hpnotiq Harmonie and Live Louder kickoff party Monday night in Hollywood. A beaming Kelly was overcome with joy when speaking about her BFF’s three-week-old daughter, Blue Ivy Carter.

“She is just more precious than a diamond. She’s just so stunning,” gushed Kelly. “I’m so happy for my sister and her husband. She’s beautiful.”

The new parents are in heaven. “She’s an incredible mother. I’m so incredibly proud of her, so proud of her,” added Kelly. “She’s in mommyville and I’m so happy for her and her husband’s in daddyville, and the baby is very beautiful.”

Check out the interview below: