What does その辺でね /"sono hen de ne" means in this context ? (A conversation on airplane between 3 sisters,while they're travelling to Japan)

Question

Context : 3 sisters are traveling to Japan .When the older sister saw her 2 little sisters are arguing with each other, she said this 「二人ともその辺でね。日本に着く前に疲れてしまうわよ」 I don't understand what does she means exactly here ( can only guess based on context that she tells her sisters to stop arguing ,but i'm not sure ) Much thanks if anyone can explain the grammar and correct meaning here of this sentence

Answer 1

Your understanding is correct.

Strictly speaking, it is the definition #2 from here:

その程度。それくらい。「―でやめたほうがいい」

The ね is an ending particle for assertion (def #3).

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I'm not sure how idiomatic it is, but "you guys should stop there" may work also in English.

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このへん has a similar meaning.

２ この程度。「―で打ち切ろう」