ByHeart has been a great formula choice for our combo fed son. We solely breastfed for the first three weeks of his life and then started breast milk bottles at 3 weeks. After a week of successful bottles once per day, we decided to introduce formula. I felt confident choosing ByHeart because it’s formulated to be the next best thing to breast milk. My son loves it! We do a formula bottle before bed and it helps him get a long first stretch of sleep. When I return to work, ByHeart will be an important part of his diet and give me some peace of mind. Thanks ByHeart!