Better get evaluated by a pediatrician
Thanks for asking on this platform
I can understand your concern.
Getting blue while crying can be due to breath holding spell or some cardiac disorder. It can be there even if there is no significant abnormality.
But this should be evaluated by a pediatrician.
I would like to know if there is any associated rapid breathing, tightening of body, unrolling of eye ball or any breath holding episodes.
I would suggest you get him clinically evaluated by a pediatrician and if needed get an Echocardiography
done for cardiac assessment.
I hope this helps.
Please let me know if you have any more questions.