Amy and Billy take Polly to a routine scan, but deciphering the ultra-sound images proves tricky for six-year old Polly. The pair continue to prepare for the twins' arrival by setting up car seats, assembling buggies and packing the hospital bag before Billy surprises Amy with a gift - a brand-new seven-seater car. Amy goes into labour, but the midwives discover a dangerous complication and Amy is rushed to theatre to get the twins out.