New mom Cardi B says she’s not ready to leave her newborn baby to go on Bruno Mars’ tour, so she’s dropping out as his opening act.

The rapper gave birth to Kulture Kiari Cephus earlier this month and was due to start Mars’ tour in Denver in September, when Kulture would be about six weeks.

But in an Instagram post Thursday, Cardi B said told she’s not physically recovered from childbirth and doctors advised that it wasn’t healthy to bring the baby on the road.

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She told her fans she “underestimated the whole mommy thing” and asked for understanding while thanking Mars for his support. On Twitter Mars said Cardi B was doing the right thing.

Cardi B’s hits include “Bodak Yellow,” ″I Like It” as well as her turn on Mars’ “Finesse” remix. She is married to Migos rapper Offset, who was recently arrested on weapons charges in Georgia.

#CardiB ❤

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