My new boots don't fit my calves- how can I fix this?

I have the same problem with a pair of cowboy boots and my dad tells me to just make a small slit in the back to accout for my, gene inherited, calves but rabbit fur boots im not so sure. U could probably look for a shoe maker or somethin to that sort and ask them abt doin the split so they could sew or do whatever they need to to keep it from damaging the whole shoe. But remember beauty aint always comfortable. lol