Nina Dixon, 31, said people are stunned when they find out she is a mum of a 15-year-old daughter, Millie, 11-year-old son, Keaton, and 10-month-old baby Harmony. The student nurse - who had Millie when she was 16 - said people constantly think she is her twin sister rather than her mum. Her youthful looks mean she has to take her ID on every night out and has even been asked for identification when trying to buy a hamster. At parents' evenings she said she’s even been mistaken for one of the pupils. Nina, a student nurse, from Darwen, Lancashire, said: “People think I’m Millie’s sister all the time and now my son has shot up it’s happening with him too. “I went to buy a hamster for my son a few years ago and the assistant asked if a parent was with us. “I laughed it off saying I was their mum, but he persisted to ask me for ID as he didn’t believe me. “I’ve had to drive back to get my ID for a glue gun before.