Baby eyelashes will naturally grow and develop as the baby grows. There's no need to take special measures to make them longer. However, if you want to help the eyelashes grow healthily, you can consider the following aspects:

- Ensure Sufficient Nutrition: A balanced diet is crucial for a baby's overall growth and development, including the growth of eyelashes. For breastfed babies, make sure the mother has a nutritious diet rich in protein, vitamins (such as vitamin A, B vitamins, vitamin E), and minerals (like zinc and iron). After the baby starts to eat complementary foods, gradually introduce a variety of foods, including fruits, vegetables, whole grains, and lean meats to provide comprehensive nutrition.
- Maintain Eye Hygiene: Keep the baby's eye area clean to prevent eye infections and other problems that could affect eyelash growth. Use a clean, soft towel or cotton ball dipped in warm water to gently wipe the corners of the baby's eyes when there are secretions.
- Avoid Irritation: Protect the baby's eyes from irritation by chemicals, strong light, and dust. When going out on a sunny day, you can consider using a hat with a visor to block some of the light and reduce the risk of eye irritation. Also, make sure that the baby's bedding and clothing are made of soft, breathable materials to avoid scratching or irritating the eyes.
It's important to note that applying various substances or using growth-promoting products on a baby's eyelashes is not recommended, as the baby's skin and eyes are very delicate and may be prone to allergies or other adverse reactions. Eyelash length is also to some extent determined by genetics, so don't be overly concerned if the baby's eyelashes don't seem very long at first, as they will continue to grow and change over time.