It was confirmed in Aug 2014 that a 4th season will not be ordered.
Emer Kenny & Scarlett Alice Johnson have previously appeared in two other television series together (although not necessarily meaning they shared scenes with each other). Namely Eastenders & the second season of Beaver Falls.
Scarlett Alice Johnson plays Laura, who has a teenage pregnancy. In Eastenders, she portrayed an older Vicky Fowler - herself born when mum Michelle was in her teens.