Are you trying to sculpt a 3D one or do you just need a pattern to cut out a cradle that will lay flat on the cake?
Here is a great cradle that is easy to make. I suggest making it out of cardboard first to perfect it and then use the cardboard as your template.
http://images.google.com/imgres?imgurl=http://www.oldvillagebakery.com/images/Specialty%2520Cakes/Christening%2520and%2520The%2520Baby%2520Cradle%2520Thumb.jpg&imgrefurl=http://www.oldvillagebakery.com/SpecialtyCake%2520Index.html&h=566&w=750&sz=214&hl=en&start=1&tbnid=e4yYU_Pr0vzAyM:&tbnh=106&tbnw=141&prev=/images%3Fq%3Dfondant%2Bcradle%26svnum%3D10%26hl%3Den%26lr%3D%26rls%3DGGLG,GGLG:2005-52,GGLG:en%26sa%3DN
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