Mom died and received money from her dead brother, if socalled grandchildren don't have proof should they reveive a full share, or the syblings inhertance

Was there a will?

No will the money was from my mom brother who died

Was there a will?

No will the money was from my moms brother who died also

Where are you? The usual line is children and if there are none, then Grandchildren. Grandchildren would not be involved in the distribution if there are living children.

Also don't understand what "so called" and "legalized" mean. Is there a question about who the birth fathers are?

I'm guessing it's "legitimate", and that there is a question of parentage involved.