The boy who announces he 'can do a pooh by myself' is played by Tayler Marshall, who plays Kenzo in later series.
Comic Relief Special aside, this is the only "proper" episode of My Family screened in 2005.
Extended episode. Length: 48 min 51 sec.
The perfume Abi sprays in Ben's eyes is called "Repulsion ...from the Roman Polanski Collection".