What are you plans for after that? Where do you all intend to live, Canada or the US? Have you started any immigration paperwork to that end?
If you show up at the border with USC husband and baby in tow, you are quite likely to be denied entry, they will basically suspect that you are attempting to enter the country to stay illegally. They don't like that obviously.
If your plan is to have your husband move to Canada and you will be sponsoring him for a spousal visa, get the paperwork started now, and most likely it will be completed within 6 months, and once he is a LPR of Canada, your visits to the US will be much easier.
For info on immigrating ot Canada see
http://roadtocanada.comIf however the plan is to have you move to the US, see
http://www.visajourney.com for marriage based immigration info
ALL the informtaion you need for either circumstance is at those 2 websites.