Little chap in a houseboat (3)

I believe the answer is:

seb

I'm a little stuck... Click here to teach me more about this clue!

'little chap' is the definition.
'Seb' can be an answer for 'chap' (short for Sebastian). I am unsure of the 'little' bit.

'in a houseboat' is the wordplay.
'in' indicates a hidden word.
'SEB' is hidden within 'houseboat'.

Can you help me to learn more?

I've seen this clue in the Evening Standard.

Want a hint initially instead of a full solution? Install my app