Sorry but I don’t have much to chip in about frames. Moreover, manufacturers are changing their frames all the time, so old wisdom (like that on Dr. Haegerstrom–Portnoy’s 2009 Info Sheet) expires quickly. Thank goodness NoIR lenses and BPI dyes are more stable.
When our daughter was 3 and 4 years old she wore Julbo looping frames and we were pleased with them. At 5 and 6 years old she wore Julbo Booba frames. (We bought them on amazon smile and directed the 1% charitable contribution to Achromacorp.) However I do not recommend them. Our daughter had a minor playground collision and her Booba frames cut her above the eye and she needed three stitches.
We’ve now switched to Rec-Specs frames. These are expensive but seem safer and better all around. At age 9 they are still working great and I recommend them.
Another kids frame recommended to us is Bolle Kids Anaconda Junior Sunglasses.
For infants, another parent recommended to me just to use the NoIR infant frames.
Remember, the key in a frame choice is to get something that doesn’t let light leak in around the edges.