1) Due to the weight of her shell, Marisa could neither jump nor move. Its body was meant for a sea creature, not for life on the surface.
For that reason, the treatment Mother Marisa gave to her children was not equal... ...and it was natural that the elder sister would think that its sister was being spoiled.
2) When they were on a walk, only the little sister would get to sit on its mother's hat. When they were having lunch, only the little sister would be carried to the table.
The mother would only take the little sister out when it wanted to pee-pee.
Only her, only her, *only her*...
-But Mawicha's cute, choo! Mawicha ish mwommie's baby choo...!!