Moral Dilemas pt.6

Nieces and Daughters
You and your family are going away for the weekend. Your daughter is 7 and is best friends with your niece, who is also 7. Your families are very close and your daughter asks if your niece can come with you on your holiday. You have been on holidays together before and don’t see any problem, so you agree.
You arrive at your holiday destination and the house you are staying at backs onto a beach. The girls ask if they can go for a swim. You tell them that they have to wait until you have unpacked the car, but they can play on the sand directly in front of the beach. They run down to the sand, and you begin to unpack the car. After about 5 minutes, you hear screaming coming from the direction of the beach and it sounds like the girls.
You run down to see what the matter is, and you discover that they hadn’t listened to you and have gone for a swim. There is no one else on the beach and the girls are caught in a rip.
The girls are really struggling, particularly your niece who isn’t as strong a swimmer as your daughter.
You swim out quickly, but when you get there, you realize that there is no way you will be able to get both the girls back into shore on your own. You realize that an agonizing decision will need to be made.
You need to decide which of the girls you will rescue first, you have enough strength and energy to rescue them both, but you can only do it one at a time. You look at the two girls, and your niece is really struggling to hold her head above water and you know if you take your daughter back first, there will be little or no chance that she will survive.
Your daughter is struggling also, but is much stronger in the water and you estimate that if you take your niece back to shore first, there’s probably a 50% chance that your daughter will be able to stay afloat long enough for you return, but you simply don’t know how long she will hold on for.