No matter what, tacit cooperation is very important for a project team. Only when everyone discusses cooperation in a friendly manner can they slowly reach a consensus. Otherwise, how can they cooperate without getting along? Therefore, it is a good way to take advantage of holidays or birthdays to interact with each other and bring each other closer. In China, feelings are the most important.
Suggestion 1: Give a business gift, not too expensive, not too simple, a good pen or a good watch, a tie or something, if you think the personal relationship is good.
Suggestion 2: Give a funny gift, such as a real doll, a cartoon statue customized with a real photo of your partner, with a big head and a small body, which is definitely a funny birthday gift.
You can also go online to look at creative gifts, all of which are very good. I hope you will like them and have a happy cooperation, haha.