Here are a few Jain-inspired birthday wishes you can use for Marasa (relative):

• Marasaji, aapko janmadin ki hardik shubhkamnayein. Aapke jeevan mein ahimsa, pavitrata, aur dharma ki jyoti sadaiv jagti rahe.
• Shubh Janmadin, Marasa! Aapki zindagi pavitra charitra se bhari ho, aur ahimsa ke marg par aapka har kadam safal ho.
• Marasa, aapko iss vishesh din ki hardik badhai. Bhagwan Mahavir ki ahimsa-gyan aapke har din ko pragat kare.
• Janmadin ki hardik shubhkamnayein, Marasa. Aapka jeevan keshari suraakhit, dharmic, aur paropakar se bhara rahe.

If you’d like, I can tailor a line to your language (Hindi, Gujarati, Marathi, etc.) or make it more formal or casual.