Jamie Lynn Spears - Holding the baby

Jamie Lynn Spears hits the shops with baby daughter Maddie Briann amid rumours fiance Casey Aldridge cheated on her while pregnant.

Although her engagement ring was still very prominent, the teen star looked cagey as she cradled the two-month tot after purchasing a new mobile phone.

Perhaps the purchase was a tracking device for Casey?

His ex girlfriend Kelli Dawson rocked the Spears family this week after telling a US tabloid she enjoyed an affair with the 19-year-old while Jamie Lynn was six months pregnant.

And her story was supported by Jamie Lynn’s sister Britney’s first husband Jason Alexander, who revealed that the fling was common knowledge in their hometown.

Casey - who is due to wed Jamie Lynn later this year - has denied the allegations.