Moana's mum: Sina

I really liked her even though we didn't get to see a lot

Just wish she got her own duet or song, you can't cast Nicole Scherzinger and not have her sing!Disney Princesses whose mothers we've seen:
Mulan
Tiana
Merida
Rapunzel
Ariel (though it was a flashback)
Aurora 
Anna & Elsa
Moana