Two female rabbits unbreakable....?

hi. I have two female rabbits both from the same mom but different litters!.one was born 5 months before the other and i put the the youngest one with her when she was around 11 weeks and theyve been living together for about 2 years now and it's so sweat the way they are it's like there unbreakable! when they go out for arun they go everywhere together it's like they've got eachothers back lol they snuggle up together when they in the hutch like now there just lying down next to eachother with there heads together with there noses kinda touching!. I just find it fascinating seeing two rabbits like this witheachother just seeing how much they love eachother!!!! and just seeing them like this puts a smile on my face lol do you think there bond will ever break? or do you think there friends for life??? and have you had rabbits that were like this? (=