Danni,

I don't use a blanket with a sleeping bag. I have three sleeping bags at any one time of different TOGs and use them accordingly, and Charlie has never been too cold. When the temp is going down to single digits, I will put him in socks, a singlet and a wondersuit, and then into a 2.5TOG sleeping bag, and he stays snuggly warm all night.

He's a big of a wriggler so blankets never worked with him, and he hated being wrapped. He loved the sleeping bags and still uses them today. In fact I just went out yesterday and bought the next size up.