When you have a newborn, the world suddenly looks a lot germier. You load up on sanitizing wipes and sprays and tuck them in all your bags and the seat pockets of your car. But here’s the thing: All the wipes in the world won’t change the fact that your little one will still get the occasional cough and sniffles as her immune system develops. So, what you can do is help build up your baby’s immunity by learning about these three lesser-known factors.

1. Prebiotics

Research has long suggested that a healthy immune system stems from a healthy gut. We all have a community of microorganisms known as the microbiome that call our digestive system home. It’s a delicate balance of different types of bacteria, and its job is to keep us healthy. At least 70 percent of your immune system is in your gut, research finds. A baby’s microbiome is still developing, so promoting beneficial gut flora is key to building immunity. Enter prebiotics. Think of these as the food that feeds probiotics, which are good bacteria (more on that below) necessary for gut and immune health. Prebiotics are carbohydrates your body can’t digest. They move to the lower GI tract where good bacteria feed on them in order to thrive.

Prebiotics are found in high-fiber foods such as onions, chicory root, asparagus, dandelion greens, artichokes, and under-ripe bananas. Babies aren’t eating these foods yet, but you can give your baby 4 months and older a daily supplement containing prebiotics, to help ensure he’s getting a healthy dose of them. Mommy’s Bliss Organic Baby Elderberry Drops contains prebiotics in the form of inulin, derived from Jerusalem artichokes, as well as immune-supporting elderberry and zinc.

2. Probiotics

These good bacteria help promote and restore the delicate balance of good and bad bacteria in the microbiome, supporting the immune system. They’re in fermented foods such as yogurt, sauerkraut, kefir, and pickles (again, not on a newborn’s menu), but you can also get them in supplements. Lactobacillus and Bifidobacterium are two of the most well-recognized strains. Mommy’s Bliss Baby Probiotic Drops contains pure Lactobacillus rhamnosus GG, the world’s most-studied single-strain probiotic, delivering 1 billion cells per serving—without sugar, dairy, artificial flavors or colors.

3. Vitamin D

Chances are you’ve heard some buzz about vitamin D and immune health. Research has shown that the vitamin bolsters immune health against bacteria and viruses (that includes those occasional coughs and sniffles), and a deficiency of vitamin D is linked to increased infections, autoimmune issues, and allergies.

The body doesn’t make vitamin D. We can only get it from our foods, sunlight, and supplements. Supplementation is especially important for breastfeeding infants because breast milk lacks vitamin D; babies that young aren’t eating a variety of foods yet; and it’s best for them to avoid direct sunlight. Daily drops can help your baby get her immune-supporting dose. Mommy’s Bliss Baby Vitamin D Organic Drops contain 400 IU of liquid vitamin D in a single drop, promoting healthy growth and bone development. Mommy’s Bliss Baby Multivitamin + Iron also contains 400 IU of vitamin D, along with vitamins A, B1, B2, B6, C, E, folate, and iron, covering your little one’s nutritional bases while providing immune support.

While baby may still get occasional coughs and sniffles, take heart: The habits you’re starting with your little one now will help him develop his immune system for the long haul. That’s nothing to sneeze at!