in the first case, you can't say that he is your brother, and you two are netizens. It's not clear what kind of software you use here. At present, many people use dating software, many netizens, and many registered software, such as WeChat, Momo, QQ, soul and so on. Everyone is unfamiliar at first, and it's impossible to say.

In the second case, a similar flower may have a similar personality to your brother. There are many people in China, and all kinds of situations may happen. If a person has a similar experience with your friend, it may lead to their similar personality, so it is normal.

from my personal suggestions, I can learn more. I prefer the first possibility.