[AntonioMQ]

mattHBCali, your idea of sending her a birthday gift and flowers for the Tham boon is appropriate. When a family get together to Tham boon for 100 days anniversary of a family member's passing, it includes going to a temple and make merit there. Friends can be involved in the celebration by giving money as mat has mentioned. So it would be confusing if you send money for Tham boon and also say happy birthday.