Missourri Quilt Company posted a new video on YouTube with instructions for a self binding baby blanket made with two pieces of flannel. She didn't use a batting in it. It is really cute and looks quick. I have made baby blankets from two pieces of flannel without batting. The flannel seems to cling together and doesn't need to be quilted together. In my opinion, babies always need a cuddly flannel blanket, regardless of the time of year. Most places are air-conditioned and often quite chilly. I think batting would be OK, if you like. Also, fine without.