Which is the best infant milk formula for babies with family history of allergy?

Pre-digested formula. There are 2 hypoallergenic formulas, nutramigen and alimentum. They are predigested to avoid food allergies. They are also much more expensive. You can probably try regular priced formulas that are either milk-free or with partially digested milk proteins. By far, most babies do well without needing a hypoallergenic formula.