だからお互いに助け合う必要があったので、そういう意味では妹との絆は強かった。

Sentence Analyzer

だから お互い 助け合う 必要 あった ので そういう 意味 強かった

English Translation

Therefore we had to help each other and in that way the bonds between me and my sister were strong.

Furigana

だからお(たが)いに(たす)()必要(ひつよう)があったので、そういう意味(いみ)では(いもうと)との(きずな)(つよ)かった。

Romanji

Dakara otagai ni tasukeau hitsuyō ga atta node, sōiu imi de wa imōto to no kizuna wa tsuyokatta.

Words

だから (だから)
so; therefore
お互い (おたがい)
mutual; reciprocal; each other
()
at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although
助け合う (たすけあう)
to help each other; to cooperate
必要 (ひつよう)
necessary; needed; essential; indispensable; necessity; need; requirement
()
indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and
有る (ある)
to be (usu. of inanimate objects); to exist; to live; to have; to be located; to be equipped with; to happen; to come about
ので (ので、んで)
that being the case; because of ...; the reason is ....; given that...
そう言う (そういう、そうゆう)
such; like that; that sort of; very
意味 (いみ)
meaning; significance
(で、にて)
indicates location of action; at; in; indicates time of action; indicates means of action; cause of effect; by; and then; so; indicates continuing action; indicates certainty, emphasis, etc.
()
topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis
(いもうと)
younger sister
()
if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)
()
indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question
(きずな、きづな)
bonds (between people); (emotional) ties; relationship; connection; link; tether; fetters
強い (こわい)
tough; stiff; hard; inflexible; obstinate; stubborn

Kanji

Readings: ゴ、 たが.い、 かたみ.に
Meanings: mutually, reciprocally, together
Readings: ジョ、 たす.ける、 たす.かる、 す.ける、 すけ
Meanings: help, rescue, assist
Readings: ゴウ、 ガッ、 カッ、 あ.う、 -あ.う、 あ.い、 あい-、 -あ.い、 -あい、 あ.わす、 あ.わせる、 -あ.わせる
Meanings: fit, suit, join, 0.1
Readings: ヒツ、 かなら.ず
Meanings: invariably, certain, inevitable
Readings: ヨウ、 い.る、 かなめ
Meanings: need, main point, essence, pivot, key to
Reading: 
Meanings: idea, mind, heart, taste, thought, desire, care, liking
Readings: ミ、 あじ、 あじ.わう
Meanings: flavor, taste
Readings: マイ、 いもうと
Meaning: younger sister
Readings: ハン、 きずな、 ほだ.す、 つな.ぐ
Meanings: bonds, fetters
Readings: キョウ、 ゴウ、 つよ.い、 つよ.まる、 つよ.める、 し.いる、 こわ.い
Meaning: strong