Growing while sleeping?

[Kodou]

So I'm sitting here and my music star is sleeping on my desk but just a few minutes ago it my Chamametchi changed into a Memetchi. Is it normal on a music star to evolve while sleeping? Or do all music star and other tamas do that?

 

[Tama65]

Yep it is completly normal it happen to me as well.

 

[Yoonha]

Of course its normal! That's one way tamagotchis can evolve.