Kei-chan is very lucky, you know. She's been that way ever since she was born.
Literal
Kei-[suffix-ちゃん] [topic-は] very luck [subj-が] good [feminine-のよ]. Childbirth [gen-の] time [from-から], that-way [copula-だったわ].
ちゃん is the diminutive/affectionate suffix. 運がいい 'to be lucky' (luck + が + good) is the standard expression. お産 'childbirth' uses the polite お prefix. だったわ is a feminine past-tense copula — the わ softens and feminizes. The sentence has the warmth of an older woman reminiscing about someone she's known since birth.