<s>[INST] okay----here goes: my 9 month old nephew s mother just found a lump under the skin of her son. He is an otherwise healthy baby and saw his pediatrician 2 days ago. He is scheduled for a c-t scan tomorrow. Can you provide any info re: how common this ism what it may be, and how likely is it that it is something serious? Thank you so much. [/INST] Hi, Welcome to Chat Doctor, The information you gave is very limited to arrive at any conclusion. I would like to know the following details:Where exactly the lump is seen? As in, which body part? When did the lump start? How has it progressed to this size?What's the size of lump? How is the skin over it? Whether you can move it or not? However, good thing is that a pediatrician has seen and ordered Ct scan which obviously would have been needed. You can get back with the details and would be able to help you. Take care. </s>