It’s intriguing but understandable that children have difficulty comprehending the ‘travelling’ concept of the first and second person.
One minute I’m me and you’re you, and the next minute it’s the other way round!
Using only the third person when talking to a child – ‘Come to Mummy! ‘ for example – is a temporary solution.
In some countries there’s no need to address the difficulty at all – in colloquial Vietnamese the words for ‘I’ or ‘you’ don’t even exist.
But the plot thickens.
For speakers of English, which mercifully dropped ‘Thee’ and ‘Thou’ some while ago, the idea of a formal ‘you’ that takes a third person verb is baffling.
‘Usted’, the formal ‘you’ in Spanish, is a contraction of ‘vuestra merced’ which means ‘Your Grace’.
Maybe if we all had a name, and just used the name or responded to it like dogs do, life would be simpler.