Me and my fiance came over this topic earlier (worst case that could happen)

Is there any one who has considered a sperm donor/ has used a sperm donor or has used a family relative as a sperm donor due to not being able to concieve naturally???

I have so many questions about it especially if it's one of those options in the future.

Would this be easily noticable to people after the baby grows up? Is it possible to pick a donor that some what resembles the father?

If anyone had knowledge on this and would like to share would be so appreciated. You can private message as well:)