I saw this on Ivillage.com
"For babies under six months of age, sunscreen may be used on small areas of the body such as the face and the back of the hands if adequate clothing and shade are not available. For older children, test the sunscreen on the baby's back for a reaction before applying it all over. Apply carefully around the eyes, avoiding the eyelids. If your baby rubs sunscreen into her eyes, wipe the eyes and hands clean with a damp cloth. If the sunscreen burns her eyes, try a different brand or try a sunscreen stick or sunblock with titanium dioxide or zinc oxide. If a rash develops, talk to your pediatrician."
There are two very important reasons for not overusing sunscreen in young babies:
1. Infants and children have what is called a high body surface to volume ratio. What this means is that proportionately babies have more skin for the size body as compared to an adult. Sunscreens are made of chemicals. On the older child and adult, the chemical exposure is relatively minimal because the body surface ratio is smaller than a baby. Therefore, babies get a higher "dose" of sunscreen than do those older. While this exposure would most likely not cause any problems, the likelihood of an adverse reaction is greater.
2. Babies have a mildly impaired mechanism to keep cool by sweating. In addition, they have a greater risk of becoming dehydrated due to heat. Sunscreen can somewhat impair effective cooling by perspiration, so placing it on an infant could be detrimental.
This should help you a little. I would get the best formula as close to a hypoallergenic with a high SPF like 45 or 50 and just put in on the cheeks, nose, head. Try and get a little sun hat and then you wont have to put in on her head, maybe just a bit on her forehead. Then maybe some on the arms and shoulders and maybe a bit on the front of the legs or where you think she will get the most sun. I think Coppertone has one called Waterbabies. That is a good one.
M.