My 9 month old granddaughter stayed with us last week and I noticed the samething especially when I was holding her in an upright postion. It was better when she was sitting, but her feet got purple again when she was in her jumperoo. I asked my daughter about it, and she said she has noticed the purple feet from time to time but didn't think anything of it. Of course, being the worry wort I am, I went on the internet and found that the condition is pretty common in infants. Their blood vessels are small and skin pretty thin so it makes their arms, legs or feet look purple due to the position they are in. My granddaughter's toenails even got purple. If you find out anymore info at your doctors appointment, I would appreicate it if you would come back and post it. There is always something to worry about with these little ones! Ann