For me I would say “The Expanse” is a huge one. If there was ever a self made family, the crew of the Rocinante is one of the best. The amount of time they spend together and how they congeal into life long partners and friends in the face of some truly awful events is really inspiring to me.
‘The Lurking Fear’ by HP Lovecraft is about family. Actually a lot of his stories are. Just never in a good way.
For a less snarky answer I’d go with the original Star Wars trilogy as a good answer. Yes, I know the meme phrase regarding this, but it’s true that what elevated the trilogy above mere space adventure was the reveal (retcon, but who is counting) of Darth Vader and Luke’s connection. It gave the entire conflict a real sense of weight. The showdown in Return Of The Jedi where Luke cracks and goes beserk, followed by Vader sacrificing himself and unmasking is really great emotional closure for that story.