Wipe Backside

Daven: Ah Gu, i wanna da bian!

Me: Dun wan la, your mum not here yet, i dun wanna help u wipe backside.

Daven: But I very urgent!

Me: Dun wan! Cuz i dun know how to help u wipe backside!

Daven: Then you da pian how (do u wipe yr backside)?

Me: - -" I know how to wipe my own backside, But i dun know how to help u!

Daven: Ok la, i sit until mummy reach k.

And that was what happen, 5min only la.