Our toddler (almost 3) at some point a few months ago stopped falling asleep by herself - now one of us needs to sit with her in her room, hold hands, etc. until she fully falls asleep. What is considerably more annoying, the same applies if she wakes up during the night - she starts shouting "I want my dad", so I have to get up, go to her, spend 30 mins or so until she falls asleep again. Usually she wakes up 2 times every night, so I am rather exhausted at this point.
I would appreciate any advice on how to break this pattern. With other things (e.g. giving away dummy, going to the nursery) we used educational books and cartoons (even about Peppa Pig when she is in her nursery) to convinced her that that's what "big" children do - but I wasn't able to find any decent material in this case.