Formal:
* आपके परिवार को ढेर सारी शुभकामनाएं। (Aapke parivaar ko dher saari shubhkamnaayen.) - This literally translates to "Many blessings to your family."
* आपके परिवार पर भगवान की कृपा रहे। (Aapke parivaar par bhagwaan ki kripa rahe.) - This means "May God's grace be upon your family."
Informal:
* आपके परिवार को ढेर सारा प्यार। (Aapke parivaar ko dher saara pyaar.) - This means "Lots of love to your family."
* आपके परिवार के लिए शुभकामनाएं। (Aapke parivaar ke liye shubhkamnaayen.) - This is a more general way of saying "Blessings to your family."
More specific:
* आपके परिवार को खुशियाँ और समृद्धि मिले। (Aapke parivaar ko khushiyaan aur samriddhi mile.) - This means "May your family be filled with happiness and prosperity."
* आपके परिवार को स्वास्थ्य और खुशी मिले। (Aapke parivaar ko svaasthya aur khushi mile.) - This means "May your family have health and happiness."
You can choose the phrase that best suits the context and your relationship with the person you are talking to.