When giving gifts, the most important thing is to consider each other's interests and preferences. Here are some suggestions that may be suitable for my sister-in-law as a birthday present for my brother-in-law:

1. Tie or tie clip: As an accessory for formal occasions, tie or tie clip is an absolutely reliable gift choice.

2. Electronic products: If Dajiefu is a technology enthusiast, consider giving him some latest electronic products, such as mobile phones, tablets or game consoles.

3. Sports equipment: If Dajiefu likes sports, consider giving him some sports equipment, such as running shoes, sports watches or bicycles.

4. Books or magazines: If Da Fu Jie likes reading, consider sending him some books or magazines that he is interested in.

5. Gift basket: If da Fu Jie likes to taste delicious food, consider giving him some delicious food and drinks, such as coffee, chocolate or wine.

In a word, the best gift is to be able to express your concern and blessing to DaJieFu and satisfy his interests and preferences at the same time.