I have been using this pattern and sharing it with Charity Groups since before 1950. It has been “borrowed” by many people since then and claimed to be designed/corrected/ improved/created and/or conceived by them. All I can say is that if you knit this little sweater for anyone, PLEASE consider knitting one for a local Charity and do not try to claim it as your own creation. Thank You.
The following are some results that I’ve achieved with different needles and yarns for different sizes, Please understand these are MY results based on my knitting tension, I just thought they might help you as a starting point. If you haven’t got the pattern, I will be putting it up on Ravelry ASAP, but you can get it on the internet in some form or other (might be correct or not) under the
name “5 Hour Baby Sweater” from many “”Originators“”

For 18” Doll=#2.75 ndle w/Sock Yarn- #4 w/Worsted
For Preemie= #5 w/Baby Yarn - #4 w/Worsted