Thanks for all the replies folks.
Meggie,
Thanks for that. Is settles an ongoing argument with my mum. She is adamant Shelby has been crossed with another dog and there is only two sizes. I actually love Shelby's size, Ford is dainty and I am a childminder so I don't want him near them incase he gets hurt. Shelby is the big bruiser who I don't worry about so much although I still keep her away from the "active" kids
I "might" one day breed with her but I need to do my homework first as I know it's not just about putting two dogs together. But then I know I would probably keep them all..... Not that keeping them all would be a bad thing