。
She'll probably take care of everything for us.
Literal
She [topic-は] our care [object-を] all do for-us [conjecture-だろう].
Three pieces work together. (1) 世話をする ('to take care of, to look after') is the workhorse phrase for caregiving — used for children, the elderly, pets, and even guests. (2) The benefactive ~てくれる marks the speaker's group as the grateful recipients of her care. (3) ~だろう adds speculative force ('probably / I expect') — the speaker is making a confident guess rather than a flat claim. すべて ('all, everything') is a slightly literary alternative to 全部.