In the fourth episode of Catastrophe's second season, Rob (Rob Delaney) tells Sharon (Sharon Horgan) that he's more proud of their relationship than their kids.

"You've got to be a monster not to love your kids. This? Maintaining this?" he says, pointing at themselves. "This is the slog."

That is Catastrophe in a nutshell. Of course, the brilliant, biting series is not an actual slog. Arguably the best rom-com of 2015, Catastrophe, which drops its easily digestible, six-episode Season 2 on Amazon Prime Friday, has not lost its touch — funnier, dirtier, sweeter and more foul-mouthed than ever in celebrating said slog.

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Season 2 picks up three years after Season 1's cliff-hanger, which saw Sharon's water break following the couple's wedding-night fight. That baby, Frankie, is about to turn 3 and the couple has a newborn daughter, Muireann, whose unpronounceable Gaelic name becomes a running joke. If you feel robbed of seeing Frankie's birth and the new parents deal with an infant, know that Horgan and Delaney, who once again penned all six episodes, came up with the arc of Season 2 first. Rob and Sharon's weeklong sex-a-thon and accidental pregnancy in Season 1 were born (no pun intended) when Horgan and Delaney later started discussing how Rob and Sharon met.

Now in the throes of parenthood, Rob and Sharon hit plenty of familiar beats: disparate appetite for sex after childbirth (he's not fond of the "sexual rainchecks"), breastfeeding problems, possible post-partum depression, when Sharon should return to work, if Rob should quit his job, how they should celebrate their anniversary (he's booked a cheese-making class; she's against it). Lesser shows would take a single disagreement and turn it into the insurmountable A plot of an episode. Rob and Sharon average about 4.72 tiffs an episode, and never once do they grate or do you think "these two need to break up already." Part of that is due to Horgan and Delaney's delicious chemistry, but it's mostly because Catastrophe is anchored in realism and the duo's acutely observed writing. It rejoices in the mundane, the everyday stupid stuff, the everyday hard stuff you just have to get through together. Like any true couple, Rob and Sharon operate on a level of bemused annoyance with each other that makes their lovely, quirky small moments all the warmer and more genuine.

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Big stuff unloads on the couple too. Sharon's dad (Gary Lilburn) is showing signs of dementia and her brother Fergal (Jonathan Forbes) has money problems and secretly turns to Rob for help. Season 2 also shares the spotlight, and gets expressly darker, with their friends Fran (Ashley Jensen) and Chris (Mark Bonnar), whose deteriorating marriage bolsters Chris to explore his sexuality. Rob's friend Dave (Daniel Lapaine), meanwhile, struggles with his sobriety, undercutting his bro-y exterior.

But the show is, naturally, strongest when it pivots back to its two leads, whose resolute lack of pretense is a truthful, welcome tonic to our overly Instagram-filtered world. The season ends with another cliff-hanger following another, albeit slightly bigger, dispute, but you hope — nay, you know — these two are too strong and too good together to collapse under whatever obstacle life throws their way. So, enjoy the slog.

Watch the Season 2 trailer below.