The season 4 Big Three trilogy concluded tonight with Kates Hell of a Week.

Weve seen Randall deal with trauma-connected anxiety andKevin strugglewith lost love and finding his path at different ages.

Lets dive into Kates bad week and the related moments from her past.

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Shes eager to get some sleep before the retreat for families with blind children.

But Toby is obsessively researching a gene therapy treatment that helped someone get 30 percent of their sight back.

But Toby stubbornly insists on researching further because he doesnt want to give up hope.

Kate is annoyed but drops the conversation.

She mentions Madison walking Audio while hes at work.A Kevin callback!

Rebecca expresses sympathy for Tobys struggles, but Kate notes she herself is struggling, too.

She needs Toby, for things like taking Jack swimming or helping him ride a bike.

Rebecca then insists they go swimming, to show Kate she doesnt need Toby.

Later, Rebecca adds that shes always there if Kate needs her.

When Kate returns home, she confronts Toby.

She demands he be the man she and Jack need.

Then Kate talks on the phone to Kevin and Randall about escaping their misery with a cabin trip.

Toby insists he can watch Jack himself while she takes some time away.

Will Toby get over his issues in that time or are he and Kate doomed?

Well, here we are.

The episode opens on toddler Kate approaching Jack after Kevin and Randall are finally asleep.

Kate imagines herself as the hero and Jack as a prince.

While that scene shows past mother-daughter tenderness, theres new tenderness in the present.

Kate readily accepting her mothers offer to take Tobys place is progress itself.

Then, they bond delightfully throughout the retreat.

During the pool scene, Rebecca notes Kate used to love swimming.

Rebecca tells Kate to let her weight literal and figurative go, to let Rebecca bear it for her.

Then Rebecca mentions the source of her Bug nickname for Kate (FINALLY!

): Its because growing up, Kate loved bugs especially lightning bugs.

Shed catch them gently, then whisper go find your way home as she released them.

Then Rebecca confesses about her health.

Kate praises Rebecca for her strength.

To cap things off they sing karaoke together.More duets, kindly?

The line foreshadows college-era Kates Marc experience.

When we first see them, Kate and Marc are at the record store.

He gives her a present and says he loves her.

She says it back, then invites him to her mothers birthday dinner.

He reluctantly agrees to go.

It doesnt go well.

Before Marc arrives, Kate tells her mother Marc is struggling with family problems.

Then when he arrives, hes late and initially disrespectful.

Further to Rebeccas chagrin, he suggests he and Kate go to the Pearsons cabin to write songs together.

Rebecca later objects to that plan and Kate freaks out.

Were getting closer to more on the start of Miguel and Rebeccas relationship and the kids reactions.

Kate walks to a gas station and calls her mom from a payphone.

Kate abruptly hangs up and rejoins him and they continue on their way.

But Rebecca determines something is wrong anyway and rallies the boys to go after Kate.

Jack then calls Rebecca the true hero, which nods to the Rebecca-Kate moments of the episode.