[G Griffin]

My dad was a boxer.............but my mum was a Jack Russell  .

[mci services]

My dad was a boxer.............but my mum was a Jack Russell  .

you must be ugly and small then

[G Griffin]

My dad was a boxer.............but my mum was a Jack Russell  .

you must be ugly and small then

No, big and ugly 

My dad was a boxer.............but my mum was a Jack Russell  .

and you are the runt of the litter

 
Only one letter out  .

[s.w.c]

My dad was a boxer.............but my mum was a Jack Russell  .

that explains a lot,