I'm tired of seeing that trope of Fugaku despising Sakura and trying to break up her relationship with Sasuke.
New trope! Fugaku likes Sakura better than his own sons sometimes and was rooting silently for sasusaku to happen. They are the platonic grumpy and sunshine trope.
Not one Uchiha knows how she did it, but Sakura won over her future father in-law to the point where he'll ask Sasuke if he's bringing Sakura to Clan gatherings. And this was before they got together.
Itachi and Sasuke are both impressed and flabbergasted. That infamous Uchiha stoicism broke the first time they saw little genin Sakura talk Fugaku's ear off. Their father did not react how they expected at all. All Fugaku did was nod and added his own comment every now and again.
During Sakura's training with Tsunade when Fugaku had to make reports to the Hokage he would visit Sakura. And when Sakura was stuck on something she would visit Fugaku if he had time. His quietness while she talked out her problems helps her think and 9 times out of 10 she solves it herself. Fugaku may have also slipped one or two older Uchiha medical/posion techniques in with her notes when she wasn't looking. He almost got caught when Kaname gave him that old scroll to give to Sakura.
When sasusaku did happen and they were getting close to marrying age Fugaku started hinting that Sasuke should teach Sakura the fireball jutsu. Sasuke was surprised his dad didn't push it earlier.
Unknown to him Fugaku knew Sasuke would teach Sakura that jutsu since their genin days. It was just after the Forest of Death and Orochimaru's attack on team 7. Fugaku was pissed that the snake man bit his son and infected him with the curse seal.
Anbu and the Uchiha Police were working together on this, after all Orochimaru not only made it into the village but he attacked rookie genins, one of them being an Uchiha.
Fugaku had gotten statements from Naruto and Sasuke. Both told him of Orochimaru's attack, how he sent a giant snake after Naruto and tried to impersonate the boy, the bite on Sasuke, and the group of Sound ninja sent after he finished his attack.
Naruto knew nothing of that last part, Sasuke began to shake every time he thought about it, a deep shame glazing over his eyes.
This lead to Fugaku talking to Asuma's and Gai's teams who had witnessed bits and pieces of the fight from the three Sound nin.
It didn't take long for Fugaku to realize he needed to talk to Sakura, the only one who was present and conscious from start to finish.
To be honest Fugaku didn't think much of the girl at first. She was civilian born, and a fangirl of his son. She won't amount to much unlike her teammates. She probably would retire early when she became a mother or go into the reserves.
Sasuke was at the station dropping something off from Mikoto when Sakura came in. And oh, Fugaku knew that soft look Sasuke was sending her. The statements of Sakura calming him down in the Forest began to make sense. His eyes fixtated on the girl's newly cut hair. The girl had cut it to free herself and defend her teammates.
Sakura spotted Sasuke when directed towards Fugaku. And Fugaku knew that look too, Sakura was afraid of his son.
Before the two teammates could say something to one another Fugaku called for the girl's attention. "Haruno, let's get your statement."
Sakura nodded and followed Fugaku to an empty room with a desk and two chairs.
Sakura retold the tale filling in the gaps of her dragging the boys away, and trying to cool down Sasuke's fever. Her setting up traps, and how the fight with the Sound nin went.
"Sasuke-kun woke up then, but. . ." Sakura began to shake. "The power that seal gave him was monstrous."
Fugaku's eyes narrowed. "You think my son is a monster?"
Sakura's head shot up. "No-"
"He defended you did he not when he woke up?"
Sakura slammed her fist on the table, Fugaku pretended not to notice the small cracks.
"That wasn't Sasuke-kun! That seal Orochimaru forced on him was poisoning him! He's not bloodthirsty, and he was shaking when the seal receded!" Sakura took a breath. "I hugged him, begging him to stop, and that's when the seal released him."
Fugaku could see it now, what Sakura was shouting at him. She wasn't afraid of Sasuke, she was afraid for him. Fugaku could see past that fear now in her eyes.
That's the moment Fugaku knew Sakura would one day join the clan, after all no one loved like the Uchiha. They are sometimes born with a different family name though.