This is more of a filler chapter. It explains a few things and shows what Garp feels, I think. I'll just let you be the judge of what everything that happens in this chapter means. I'm not sure if I actually got my idea through in this chapter but I still hope that you enjoy it.
Garp found Smoker on the top of a large building, looking angry at the world. If Garp had to guess, his recruited search party had escaped. Sighing, he sat down and pulled out the paper with the picture of his grandson on it. It wasn't much but it was something that kept him going. Ace and Sabo were on the paper as well. All three of them, well almost all three of them, had impossibly large grins. He had it taken when he called for his three grandsons to come to Marineford when there was supposed to be a bad swarm of creatures for that month.
Luffy didn't want to go, afraid that his friends were going to be eaten, Ace just didn't want to go anywhere with Garp, and Sabo didn't want to push his brothers into doing something that they didn't want to do even if it was safer to do it. In the end, Garp basically kidnapped the three and dealt with a month of two of them hating him and the third scolding him for taking them without permission. It was not a fun month.
But Garp now had this picture of the three of them. Grinning sadly, a few memories of Ace and Luffy as babies crossed through his mind. Then the inevitable meeting between Ace and Luffy. Finally, when he came back to train his dear grandchildren only to find that Ace and Luffy had another brat with them. His first meeting with Sabo was also his last meeting with the three where they were in the safety of a home.
Garp flinched inwardly when he remembered coming upon the house in shambles and not a soul in sight. It was obviously a creature's work, but since there were no signs of a fight or a struggle, Garp could only guess that the residence were safe.
He didn't see the kids again until two years after finding the house destroyed. They were alone, sort of, but fully capable of taking care of themselves. Garp had a talk with them, probably the most humane talk he ever had and will have with them. He decided to leave them to their devices and trust their judgment. Thinking back on how much trouble the three had both caused and gotten into back at the Marine base, it had been a good decision.
Sengoku didn't agree and tried to convince Garp to bring the three there so that they could be watched after and raised to be Marines, especially Luffy, but Garp had declined. He might have wanted to turn them into Marines, but he didn't want them to have a sheltered life or to have Luffy find out what he was capable of. He was already showing signs that his gift was going to be stronger than his mother's. No, Garp didn't want Luffy or the other two to be kept locked up in some room when there was the whole world to explore.
The only reason he had changed his mind was because Ace and Sabo had died. Though Garp knew that Luffy would be able to take care of himself, he didn't want his last grandchild to be alone. After all, even if he didn't show it properly, he loved the three brats more than anything in the world. It was heart breaking to see Luffy broken in a place that no one could heal.
Then he had to go and pull a stupid stunt and come to Loguetown. Why he had come to Loguetown was beyond Garp, but he had a fearful suspicion about the reason and didn't want to be right. If he was right, just letting him roam around the base would be difficult if not impossible.
Yes, Garp very much-loved his grandchild, but sometimes, he could be more of a handful than his fully grown criminal father. Garp growled at himself. He was not a fan of thinking of his son. Sure he loved the idiot, but it was too much of a headache to actually think about the idiot. Sure, he was one of the smartest people Garp knew, but the path he decided to go down was what made him the dumbest person alive.
Sighing, Garp stood. He wasn't going to get anywhere just sitting down and moping. He had a grandson to find and he wasn't going to let something as trivial as two people who would rather incur the wrath of a Marine then find one lousy kid stop him from finding said kid. He wouldn't let Luffy be alone, and he most definitely wasn't going to let the kid go off on a fool's errand to die. Leave it to the son of two eccentric people to end up running into some crazy old man that can't keep his mouth shut to save his life.
The kid was after something really dangerous. Stronger men have died just for whispering its name. Luffy might have the ability to charm people onto his side without meaning to, but that was an ability he inherited from his mother. He also inherited her small stature and never aging face. The only thing he got from his father was his never-ending will, though Garp may have contributed to that, and his intelligence.
Now, to the common eye he may seem like a complete idiot, but he is smarter than he acts. Though it isn't common sense smart or everyday knowledge smart, the latter was mainly due to living out in the desert, but he was able to take one look at a situation and see the bigger picture and the over-all need to accomplish his goal.
Yes, some people might call it stupid, but Luffy also sees what he himself must do in order to accomplish his task. Garp had witnessed that ability himself once. It was when he was going to collect the three brothers and take them to Marineford when he saw them struggling against some sort of eight-legged creature. It wasn't going well and Garp was about to jump into the fray when Luffy did this weird thing with his arm and made it grow. That was also the first time Garp had realized that Luffy had eaten one of the Devil Fruits. Garp wasn't sure why he was surprised that Luffy had eaten a Devil Fruit though he wasn't sure why it was such a shock, but not as shocked as Luffy was when his little trick actually worked. No matter the shock, Luffy had given Ace and Sabo the chance they needed to kill the thing. Not perfect but still a good first try.
Yes, his bumbling grandson is smarter than people give him credit for. His blank look while he follows the green-haired swordsman that Garp had asked to help look for him isn't actually blank but full of knowledge that people who have lived in the safety of the cities will never know - "LUFFY?!" What is that idiot swordsman doing with my grandson?