The ending of the first episode when Mike and the kids come to get Frankie after she was left stranded in the middle of nowhere by the woman she was trying to sell a car to who had three kids in jail.
Also, this line that Frankie says at the end:
Frankie: [voiceover] That's the thing about family. Sure, they eat your food and wreck your face and you've got to save them a thousand times a day from who knows what. And every now and then they save you.
The ending of "Thanksgiving" where it turns out that Frankie's family made thanksgiving dinner for her so it didn't have to be cancelled when she had to go to work for Mr. Ehlert that day so she didn't have to do all the cooking like she usually does.
In "Bad Choices", the Hecks aren't sure whether or not they should move into a Hickory Arms apartment. For example, Frankie seems to like Hickory Arms because it has more luxuries than their old home and their roof was broken, but Sue doesn't want to leave her friends and the other neighbors they knew. At the end of the episode, the neighbors come to help the Hecks fix the roof of their house, making Frankie realize that they truly belonged in this neighborhood that they were lucky to have to count on for help.
Frankie: [voiceover] You see, the thing we've forgotten is that we're part of the neighborhood. And the more our neighbors showed up to help us, the more Hickory Arms became a distant memory.
Axl's usually a total Jerkass, constantly complaining and barely ever showing affection. But in "The Break-up" he falls in love with a girl named Morgan. For days, he's bubbly because he's so in love. It's sweet to seem him so happy when he's usually so whiny and rude. Given the title of the episode, you'd know where this is going. Axl is heartbroken. Regardless of him being emotionally distant all the time, he breaks down and lets his mother hug him.
Frankie: Oh god. I forgot how soft his skin was.
"The Clover": Axl comforts Ashley after her date dumps her at the prom.
"Hallelujah Hoedown" has Ashley returning the favor the next year as she steps in to dance with Axl right after Cassidy dumps him and he's named "Prom King".
For six seasons, a Running Gag has been Sue completely oblivious to how obviously gay her one-time boyfriend Brad is despite how everyone else can see it. Then in "Risky Business", Sue tells him what a great friend she considers him, and Brad suddenly becomes nervous and tells Sue that he wants to tell her something...but Sue just puts her hand on Brad's, smiles, and simply says "Brad. I know." They then share a warm hug.
In "A Tough Pill to Swallow", Sue forgets to renew her financial aid for college, and the only way to get into college is to pay the full amount. So Mike sells his half of the sports team diaper business to get the funds to put her through.
In "A Very Marry Christmas," Bill Norwood unexpectedly gives Mike a Christmas gift, a pair of sunglasses. Mike, not used to people doing things for him, feels uncomfortable with the gesture. He tries to find a gift to give in return, but can't come up with anything good, and the whole thing gets worse when he finally tries the sunglasses on and is forced to admit they look really cool (and Frankie agrees). Finally he can't take it anymore, goes over to Bill's house, and insists on giving him the money he spent. Bill doesn't want to take it, but Mike is adamant, so he does. Mike walks back out to his motorcycle, and Bill calls after him, asking if he at least likes the sunglasses. Mike looks back, the sunglasses now on, and says, "I love 'em." He gets on the motorcycle and rides off, and Bill just watches him, smiling.
"Swing and a Miss": Lexie gave up her trip to the Bahamas to get the chance to be near Axl. Goes to show how much she has really grown to like him.
Lexie's continuous attempts to be close to Axl throughout the break, despite the increasing amount of ailments she suffers.
After finding out Lexie has feelings for him, Axl goes to the St. Patrick's Day party that he said he definitely would not go to just to find her.
"Exes and Ohhhs":
A bit of a retcon, but before he runs into Devin, Axl calls out to Lexie when he sees her across the room.
Axl forgets Devin and Cassidy are there for a moment when Lexie shows up and he impulsively tells her she looks good. Flattered, Lexie thanks him.
Axl's conversation with Devin about why they didn't work. Despite not staying together, the two show how amiable they still can be.
Axl and April mostly part on good terms, until they end up stuck on the RV when Sue hijacks it and April's feelings quickly grow into resentment.
The purpose of the episode seems to be of Axl cleaning out the baggage he had left with his past girlfriends so that he could free himself up before even considering being with Lexie.
"The Par-Tay": Axl leaves the restaurant after Brick's speech about getting his bookmark before its too late, goes to Sue and Lexie's apartment and when Lexie answers the door, Axl kisses her. On top of that, after he comments on her not brushing her teeth, Lexie proceeds to turn and run, but then Axl dramatically pulls Lexie back in a sliding motion, says that he doesn't care and then kisses her againregardless.
"The Confirmation": Crossed with funny, but all the scenes of Axl and Lexie sneaking around and passionately making out each time are this. The two are so into each other that they can't keep their hands off each other.
Becoming increasingly uncomfortable with the secrecy (that was his idea in the first place), Axl finally declares to Sue and Brad (and one of Lexie's classmates) that he and Lexie are together. Along with the grand gesture of Axl caring enough to fight for her and not wanting to lose her, Lexie's reaction alone in which she cups her hands over her mouth with both excitement and surprise qualifies as she can now freely tell others about being with him as she wanted to to begin with.
Doubling as CMOF: Sue's bipolar reaction to finding out Axl and Lexie are together. While clearly uncomfortable with the idea, she's also glad that the two have found happiness together.