Praise be to Allah.
He does not deserve that, and it is makrooh to say “Yarhamuk Allaah” to him. It was reported in the two Saheehs of al-Bukhaari and Muslim that Anas (may Allaah be pleased with him) said:
‘Two men sneezed in the presence of the Prophet (peace and blessings of Allaah be upon him). He said “Yarhamuk Allaah” to one of them and not to the other. The one to whom he did not say it said, “So and so sneezed and you said, ‘Yarhamuk Allaah’ to him, and I sneezed but you did not say it to me.” The Prophet (peace and blessings of Allaah be upon him) said: “He said ‘Al-hamdu Lillaah’, and you did not.”
According to Saheeh Muslim, Abu Moosa al-Ash’ari (may Allaah be pleased with him) said: “I heard the Messenger of Allaah (peace and blessings of Allaah be upon him) say, ‘When one of you sneezes and says “al-hamdu Lillaah”, then say “Yarhamuk Allaah” to him, but if he does not say “al-hamdu Lillaah”, then do not say “Yarhamuk Allaah” to him.’”
In Saheeh al-Bukhaari it is reported from Abu Hurayrah (may Allaah be pleased with him) that the Messenger of Allaah (peace and blessings of Allaah be upon him) said: “When any one of you sneezes, let him say ‘Al-hamdu Lillaah’ and let his brother or companion say to him, ‘Yarhamuk Allaah.’ If he says ‘Yarhamuk Allaah’ to him, let him say, ‘Yahdikum Allaahu wa yusliha baalakum (May Allaah guide you and reform your thinking).’”
Comment