Why didnt he tell his mother that he had inflammatory rheumatism stolen day?

He may have chosen not to tell his mother about his inflammatory rheumatism because he didn't want to worry her or burden her with his health issues. Additionally, he might have felt ashamed or embarrassed about his condition, leading him to keep it a secret. Alternatively, he could have believed that she wouldn't understand the severity of his illness or that he could manage it on his own without her support.