Britney Spears' cousin ALLI SIMS has hit back at reports the pop superstar is a terrible mother, despite rumours she quit as the singer's assistant over the way her sons were treated. Tabloid reports suggest Sims is now helping Spears' ex-husband Kevin Federline win custody of the boys, Sean Preston and Jayden James - giving up first-hand knowledge of her cousin's mothering skills, or lack of them. But Sims insists the stories simply aren't true and Spears is a great mum. She tells People magazine, "She's a wonderful mom and she is so hands-on. Britney loves those babies to death. And they adore her." Sims also insists she's still close to her cousin, despite quitting as her assistant: "I love her, she's beautiful inside and out. We're still great friends."