This is useful to practice; look at how the two central characters are framed differently, and how editing when each is talking is quite markedly different - they're not represented as equal. One seems more central to the drama; the conflict is his conflict over what to do with his brother, how to cope with the issue of hiring a carer or continuing as his carer. The disabled character is often off-frame even when talking; the OTS shots when he's talking are a little unusual, and the editing choice is not to focus on him when we'd generally expect him to be central to the shot sequence. Okay, reaction shots are not unusual, but this goes further in the way it excludes him, makes him of secondary importance. The shot as they exit the shop is telling: as the wheelchair disappears off frame we stay with the other brother, centrally framed in a MCU.
Nonetheless, there are several two shots used to signifiy their bond and togetherness, and the 'defective gene' joke is used for exposition: to inform us of how comfortable they are with each other (although the disabled character does get cross at his brother for seeking to include him in flirty banter, sternly telling the cashier that his brother seeks to ignore his condition). The odd thing here is that the brother's actions are actually quite positive, but the editing and self-pitying dialogue from the wheelchair-bound character, reduce this to a narrative about the jumper-buying brother and his issues; his brother is only really providing signifiers about his emotional state.
You'd look out here for basic aspects of continuity editing, plus realism codes, amongst many other aspects...
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