Michelle Williams — Blue Ivy Has ANOTHER Famous Babysitter

Michelle Williams wants to make one thing clear — babysitting for Beyonce“s baby girl is just a part-time gig … because she”s not the only Destiny”s Child singer doing diaper duty for Blue Ivy.

Last night in NYC, Michelle revealed Kelly Rowland also pulled a shift watching B.I. in Beyonce”s hotel suite … during B”s concert in Atlantic City last weekend.

In the middle of the show, Beyonce thanked Michelle for babysitting — but Michelle “fessed up to us she had some help … and even got to go downstairs to see some of the show.

Music royalty for parents AND smoking hot nannies Blue Ivy wins again.