Need advice on treating flea infested pups and mother

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My mother's neighbor has a pit bull with 4 10 week old pups. All are very infested with fleas. Their skin is covered with scabs. I have offered to bath and treat them. I am looking for suggestions on how to treat them. I assume the first step is to bathe them in some sort of flea shampoo. What about a follow-up rinse with a skin/coat conditioner? Would K9Advantix be safe for the pups? Their website says it is safe for pups 6weeks and older. Thanks for your feedback.