Who is this? -- This is YOURS!

English

Possessives are often used in place of nominals in predicative phrases.

-Who is this in the picture?
-This is mine [=me] / -This is Daddy's [=Daddy] / -This is yours [=you]

English-speaking children tend to master nominals before possessives. So they say. At any rate, Hannah is doing the opposite. Why? And why substitute at all? Something to think about.

She doesn't do this to any other nouns though...

This is Mike. (NOT "This is Mike's".)

...except for her own name: "This is Hannah's" (="This is Hannah").

Why the exception? Her 3-year old mind must be treating her name (along with the "names" of her next of kin: Mommy and Daddy) as a pronoun (Hannah = I). Here is a misused first-person singular verb to prove this:

Ханна буду смотреть телевизор. [=Hannah am gonna watch TV.]

Russian
Same thing but she uses her name a lot instead of "я" to talk about herself.

-Это мамина/папина [=мама/папа].
-Это Ханна (instead of "это я").

French
No such issue.

C'est moi. (This is me.)
C'est a moi. (This is mine.)
C'est Maman. (This is Mommy.)

Since she makes no substitution of possessives for nominals in French and no mistakes in this domain, does it mean she is more advanced in French or is it because French possessives (in predicative structures) require two words (e.g. "à moi") so there is no shortcut anyway? Or is the preposition "à" such a strong marker of case that it leaves no room for confusion?

That being said, she often uses the French "je" in place of English and Russian pronouns.

Je vais играть. (Also "Hannah va играть" -- but her name gets pronounced in Russian here, not in French!)
Je буду танцевать.
J'ai peed.

COMMENTS:
* "This is Hannah's" VS "Это Ханна" BUT "Это мамина" OR EVEN "Это Mamma's". I suppose "Ханнина" is too much of a challenge phonetically. The Russian palatalized alveolar sonorant [n'] definitely takes a well-trained mouth to pull off.
* "Я" is her least frequently used personal pronoun while "je" is most common (even if she has to cross the line and mix languages). The English "I" is somewhere in the middle. Could be a reflection of how her competencies in the three languages rank compared to each other.