DS loves aliens and time machines and suchlike but has never seen Dr Who. He's now becoming aware of it through friends, comics etc and he'd love it, but I'm not sure if he's old enough - he's 5. He does well with most U/PG films and isn't easily scared, he likes Horrible Histories and so on. But DP is worried he'll have nightmares. Do you think it's too scary for 5?