Thanks for your reply yes I'm new here. And just wanted to ask how do other rabbit owners deal with rats. The kits are now 3 weeks old, but the ones who died were when they were still 2 weeks. I also suspect the deaths could've been many factor(rats and overfeeding).
Here is what happened from the start. We have 3 female rabbits and 1 male and they were all doing fine together. One of the female rabbit had 8 kits and one day I saw big rat(probably mother rat) eating the rabbit food beside the pen. I then tried to capture it with a rat cage since I thought it might go inside their pen and eat the babies(even though it probably can't since its too big to squeeze itself inside the chicken wires) and so everything went nice and all until a few days past and I saw these 2 small rats eating one baby rabbit, because the rats were able to get inside the rabbits' pen. The rats are also baby rats probably 4 weeks old, so they were able to fit inside the chicken wire.
After 2 weeks, I noticed the doe doesn't want to nurse her kits. Every time the kits walk and tried to get some milk, the doe moves away from them. The doe looks very stressed out and I initially didn't know if it was just because she had 7 kits to fed. Then one night I saw the other adult female rabbit always bullying the doe. That was when I suspected that the doe was stressed out because of the other female rabbit. They other rabbit would chase the doe around the pen. So the doe just hides inside the other house(they have 2 house, the kits are on the other side). She can't eat because every time she tries to eat the other rabbit will attack her. That's when I decided to give them abundant food. I just basically threw everything in there, 2 boxes full of alfalfa hay, pellets and veggies. They eventually stopped fighting so I suspected the other rabbit was only trying to compete for food. I went to sleep peacefully thinking they were ok now, then when I woke up the next morning two kits were dead. Did I just overfed them?
Then after coming home from work I saw another kit dead and I decided that we'll clean the house tomorrow morning. Next morning the kit that just died last afternoon, it's head was already gone and there were still a bit of blood. We suspected the rabbit took advantage and scavenged the dead kits.
Only 4 kits remain, we created another pen for them with just them and their mother. The doe has now started to grow its hair back and is starting to look better again. I also noticed she doesn't move away from the kits when they try to get some milk from her. I hope everything goes well from now. But it was just unfortunate for the other 4 kits