What Could Pimples On Eye In Children Suggest?

hi my three year old son has like a pimple looking thing on hiseye its right on his eyelashes and it wont go away i went to his doctor and he said it was like a tumor and no one would do surgery on it cause ita a sensitive area i somehow believe hisdoctor is wrong he didnt study it he just stared at it what do you think it is?