Red blotches on skin
a seven month old baby has red blotches that we can not get rid of.
I'd say take your baby to the doctor since it isn't going away. Your baby could have a rash or something and you want to be on the safe side. He could prescribe medicine to give the baby to make it better.
the baby could be allergic to something. You should go to a doctor
It is probably just birthmarks. Most children grow out of it. don't worry.
Allergies. Take your baby to be tested.