。
She welcomed the guests warmly.
Literal
She [topic-は] guest [object-を] from-heart welcomed.
心から ('from the heart') is the standard intensifier for sincerity — 'truly, wholeheartedly, sincerely.' Built from 心 ('heart') + から ('from'), it pairs naturally with verbs of emotion or expression: 心から感謝する ('thank wholeheartedly'), 心から愛する ('love from the heart'), 心から謝る ('apologize sincerely'). 迎える ('to welcome, to receive, to greet on arrival') is the standard verb for hosting — its visual is meeting someone who has just arrived, almost always with positive intent. Hospitality (おもてなし) is a celebrated cultural value in Japan, captured in everything from ryokan service to the precise phrasing of 'welcome' phrases like いらっしゃいませ.