。
She has strong affection for her younger brothers.
Literal
She [topic-は] younger-brothers [to-に] strong affection [object-を] is-holding.
愛情を抱く ('to hold affection') is a literary expression — 抱く here means 'to harbor/hold' (an emotion), not 'to hug.' 弟たち uses the plural suffix たち, indicating multiple younger brothers. 強い愛情 ('strong affection') gives the sentence an earnest, written quality.