
If it were me, I'd stay with my bitch and puppies. It's unfortunate that this wedding is when it is, and it might be different if you could just get a sitter for the day (depending on how mum is with strangers around her puppies) but to be away for several days - no way, as far as I'm concerned. What would you do if you get a phonecall to say it's all gone pear-shaped?
Others may disagree but this is my opinion.