Why out of all my siblings, do i have to most of the cleaning around the house?

ok so i have a little brother,older brother, older sister and out of all them i do the most work around the house!!my mom works and when she comes home and there's a mess she blames me!!!She say"why didnt you wash the dishes" nag nag nag nag!!! even though i wasn't the one who put them there....it jsut irritates me becasue my older brother is a16 and hes a fat lard who play GTA all day on his computer,he does horrible in school and he doesn't have to do sh*t around the house......my little brother is 12 and im 13 and he barley has to do crap!!!my sister works so i can understand....but i feel like she favors my brothers and when i ask why dont they have to anything around the house she tells me to be quiet or shutup and compares me to my cousins saying they never complain when they have to clean...but i just find it not fair!!