Beyonce Knowles is a babysitter to her sister Solange's son.

Solange often lets her pop superstar sibling look after five-year-old son Daniel - her child with ex-husband Daniel Smith - because she's so good with him.

She said: "Beyonce's very hands-on. I've had two weekends where I've been able to hand him over, and it's been very nerve-racking for me, but she does a great job."

Singer Solange also revealed Beyonce and her husband Jay-Z love spoiling Daniel when he stays with them.

She told America's OK! magazine: "They actually request him more than I'm willing to give him. But the bedtimes we got to work on. Sometimes I'll call expecting him to be asleep, but he's still up!"

The 'Halo' singer - who married rapper Jay-Z in a secret ceremony in 2008 - has always been very reluctant to speak about their home life, but Solange says they are a perfect match and Jay-Z makes a "very good uncle" as well as one that is "pretty cool".