In "The Cure," a powerless and partially amnesiac Ben Grimm watches the team disappear during a fight on TV. He immediately heads out to help them.
"I may not have any superpowers, but Ben Grimm never leaves his team behind."
The first thing amnesia!Ben does when he sees Johnny on fire is to try and put the flames out, even though Johnny has just been insulting him. Awww.
In "Scavenger Hunt," after the latest effort against Terminus fails, the others take the possible end of Earth incredibly lightly - dumbfounding Reed.
Reed: What is the matter with you three? You're making jokes? Everything we tried was useless. All the foes we faced... Doom, Annihilus, Super-Skrull - we've always beat them, but this? This is different. Terminus is unstoppable! How can you not take this seriously? Sue: Because it's you, Reed. You'll come up with something. Johnny: Y'know how many times you've let us down? Ever? About... zero! Ben: There's always a way. You know who told me that? You did, Stretch, so let's get out there and clobber this guy. Reed: Thank you. (The team put their hands together) Now let's go clobber this guy!
In the very first episode, "Trial By Fire," Johnny is imprisoned and put on trial by the Kree for destroying their sentry robots (he thought they were attacking), with Reed as his lawyer and Sue and Ben as witnesses for the defense. Ben's reaction to being summoned without warning and seeing Johnny?
"I see Stretch found ya, Matchstick. And you're in trouble as usual." *punches his fist* "Who do ya want me to hit first?!"
And when the testimonies aren't enough and Johnny is found guilty, both Sue and Ben immediately step up to defend him physically against his executioners, followed by Reed, whose only comment is "so much for fostering interplanetary relations." Even when warned that this will mark them as enemies of the Kree and get them executed along with Johnny, the Fantastic Four stick together — it doesn't even occur to them not to.
Johnny also has a moment like this in the episode. When he hears the above proclamation, he tells the other three, "I caused this, you guys. You don't have to go down with me."
The whole episode *Doom's Word is Law*. Bruiser's gotta be one of the most adorkable, human robots ever.
Arguably most of all when he dives into open air with some of the most touching Last Words ever spoken by a robot: "No. No destroy Ben."
The end of "Contest of Champions". To summarize, Ben, the last member of the team standing, has just won the titular contest. The judge, a Sufficiently Advanced Alien, offers him anything he asks for, suggesting heavily that he'd want to use it to get his humanity back. But Ben turns it down and instead wishes that everyone who lost the games should be released, starting with his teammates.
Also, while Ben is still fighting—and getting mauled—Reed asks the Grandmaster to let him take Ben's place and begs Ben to stay down. Mr. Fantastic's last plan fell flat, and it doesn't seem likely that he has another one—he simply doesn't want to see his stubborn friend get beaten to death in front of him.
A Ship Tease example from "Hard Knocks": the other three come up to Reed's lab to find him unconscious on the floor with The Hulk towering over him. As Johnny and Ben attack the Hulk, Susan hovers over Reed, cradling his head in her lap.
Later, when Ben tells Bruce that, "Us monsters have to stick together." It doesn't necessarily fulfill the intended purpose, but it's the thought that counts.
Which is followed by Bruce telling him that the Thing is a hero to millions, nota monster.
Johnny telling Reed that it was actually Ben who saved the day ("Molehattan") and then resisting the urge to steal his spotlight when the kids come over.