、。
She's cheerful, so everybody likes her.
Literal
She [topic-は] cheerful is [because-ので], anybody [from-から-も] is-liked.
ので gives the reason — softer and more matter-of-fact than ~から — and the second clause flips into the passive 好かれる ('is liked') to keep the topic 彼女 in the spotlight as the patient. The agent is dressed up nicely: だれからも = 'by anyone (and everyone),' with the pattern 疑問詞+でも/も functioning as a universal quantifier. 快活 is a slightly formal word for 'cheerful, sprightly, bright-spirited' — more bookish than 明るい and often used in character descriptions in writing.