Mercury rules 6th and 9th house is in 7th house in Cancer

As per Jyotish astrology, the placement of Mercury in the 7th house of a Cancer sign indicates that the native will be highly intelligent, intuitive and communicative in their personal and professional relationships. They may have the ability to influence others with their communication skills.

Due to the emotional nature of Cancer sign, the placement of Mercury in this sign may bring a sensitive and emotional communication style in the native. They may be highly empathetic to other's needs and emotions.

The placement of Mercury in the 7th house also indicates that the native may have a sharp intellect and good analytical abilities, which will help them to assess the situation quickly and make informed decisions.

The placement of Mercury in the 7th house is also beneficial for professional relationships as it brings diplomacy and tactfulness to the native's communication style. They may be able to negotiate and make compromises in a diplomatic way.

However, if Mercury is afflicted by malefic planets, the native may face difficulties in their personal and professional relationships. The negative influences may bring arguments, misunderstandings and conflicts with their partners.

Overall, the placement of Mercury in the 7th house of Cancer sign brings intelligence, diplomacy, empathy and intuition to the native's communication style, which can positively influence their relationships.