My fiances little sister has been sick wit pneumonia for about 2 and half weeks...?please i need help?

my fiances little sister has been sick wit pneumonia for about 2 and half weeks and cps is allover us(i live wit him) and there trying to take his sister b/c she i guess snuck out side idk if she was sleep walkin or not but stayed outside all night there sayin we dont watch them close enuf we were asleep we thought she was to how can we keep them from takein them