The Saturdays: It's not the same without Rochelle
The Saturdays played Radio 1's Big Weekend without bandmate Rochelle Wiseman, who's recently given birth.
Una Healy said: "We do rehearse as a four. We've done a few shows now so we're getting used to it. It's never the same without Rochelle, without any member there."
Frankie Sandford, who's currently pregnant, also said she forgets about her baby bump when she started performing.
They were speaking to Newsbeat's Nesta McGregor.
Biffy Clyro and Bruno Mars are headlining Big Weekend on Saturday and Sunday.
Coverage of Big Weekend is on BBC Radio 1 and 1Xtra, BBC Three and online at the Big Weekend Derry-Londonderry website. You'll also find videos and photo galleries there.
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