Below is how you start constructing this block.
I did a little research and found a free pattern you could use. Just click on the link below.
http://www.mccallsquilting.com/qb/mccallsquilting/pattern_407/index.html
I also found Delaware Quilts Block of the Month you might enjoy.
http://delawarequilts.com/BOMs/DoveInTheWindow/index.html
I hope you have enjoyed "Doves in the Window" quilt block and will give it a try!
Carolyn