[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/Your-Sisters-Sister_1124.jpg]]

A 2011 American dramedy film written and directed by Lynn Shelton, starring Creator/EmilyBlunt, Creator/RosemarieDeWitt, and Creator/MarkDuplass.

Iris invites her friend Jack to stay at her family's island getaway after the death of his brother. At their remote cabin, Jack's drunken encounter with Hannah, Iris' sister, kicks off a revealing stretch of days.

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!!This film provides examples of:
* AllLesbiansWantKids: Hannah, though averted with her ex, Pam.
* TheBabyTrap: The sex that occurs between Jack and Hannah? He doesn't know it at the time, but he finds out later that the condom Hannah provided was only meant to look like a condom, but not act like one. Jack freaks out, but after an extended quasi-SadTimesMontage where he has a lot of time to himself to reflect, he decides that not only is it worthy of a joke, but also that he is willing to be in a platonic relationship with Hannah to help raise the kid.
* IncompatibleOrientation: Jack admits to Iris that he's in love with Hannha because he knows he can't have her. This upsets Iris.
* IfItsYouItsOkay: Hannah is a lesbian [[spoiler: but still offers to sleep with Jack because she is drunk and wants to have a baby]].
* LastDisrespects: Played with. The heart-warming story told at the memorial party about how Tom was inspired by ''Film/HotelRwanda'' to volunteer at a shelter in Seattle goes over well with everyone except Jack, who thinks that remembering his brother's virtues and ignoring his faults is this trope. Jack's own story meanwhile, which toasts the cynical realization his bullying teenage brother had upon watching ''Film/RevengeOfTheNerds'' that he'd need to act nicer to have people like him, is viewed as this by the rest of remembermancers.
* LikeFatherLikeSon: Upon discovering that Emily's father had a habit for jumping from partner to partner, all of whom were of a certain ''type'', Jack points out the parallels to Emily's own penchant for formulaic flings with floppy haired, skinny-jeaned boys.
* NotEvenBotheringWithTheAccent: At first it seems as though either Emily Blunt or Rosemarie [=DeWitt=] are guilty of this as both use their own accents despite being siblings. However, it is later revealed that this is due to their age gap and the fact their divorced father emigrated to England.
* SadTimesMontage: A fairly long one while Jack comes to terms with his own issues, and Iris and Hannah overcome their own falling out.
* SiblingTriangle: Iris/Jack/Hannah. Iris, is in love with Jack, who is attracted to her sister Hannah.
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