、。
We look out for each other — give and take.
Literal
We [topic-は] mutually watching, give-and-take [copula-ですよ].
持ちつ持たれつ ('supporting and being supported') is an idiom for mutual dependence — the つ...つ pattern pairs two complementary actions into a balanced whole (cf. 行きつ戻りつ 'going back and forth'). お互いに ('mutually') reinforces the reciprocity. The sentence celebrates a cooperative relationship with a compact four-character expression.