The singer and UK X Factor judge said her former Destiny's Child bandmate and her husband Jay-Z will never have to worry about childcare thanks to Aunty Kelly.
'I am so happy for her and her husband,' the 30-year-old told MTV News.
'First it was Julez,' she said of Beyoncé’s sister Solange Knowles' six-year-old son. 'Now it's a new baby on the rise. It's gonna be so exciting.
'I get to babysit, yes!'
But she hasn't been bitten by the baby bug herself yet.
'I'll help take care of my 'sister' and her husband's baby first. I'm not ready for babies yet. I can watch them take care of this little baby.'