Ours isn't 3 yet but she puts her dirty stuff (and ours) in the sink too, when we are doing washing up she puts the clean dishes away (in mostly the right places), she helps water my plants, wipes the baby's face, fetches things for me, puts her big sister to bed, tells us when it is bath time, tells us when the baby is grumpy or stinky, tries to change the baby's nappy, tries to clean up any messes she makes, helps serve dinner, attempts to feed said dinner to the baby (who is a week old), tells her big sister to be quiet/sit down/eat up/behave at perfectly sensible moments etc etc etc. Basically she's incredibly helpful.

Big sister's helping list extends to putting toys in the lounge away IF she is severely prodded (she gets paid $5 for this), and sometimes even puts her dirty clothes in the wash before she runs out of underwear. Big sister at 3 was no help at all, she just hung around talking. Considering nothing much has changed with big sister I'm hoping the helpful streak stays with the little one