Is this normal?

Iliana • V•VIII•MMXVII 💙👶🏼 X•III•MMXX 💙👶🏻

I've searched for it but I haven't found anything of this type of "rash" or whatever it is. Is this normal? Or what is this?? I have his drs appt in 2 weeks so I'm going to ask him about it but I want to know if some moms know what this is, if it's normal on a 3 month old? He has some also on his other leg.