I feel really bad for you, I imagine that would be really hard. Especially when nobody gets a chance to say goodbye.
I was thinking about this exact type of situation lately, and I've actually gotten myself pretty worried about it. I'm fairly new to this and I haven't had to deal with anyone leaving. I've got great families. I don't actually foresee any reason that they would leave, but obviously things can change without any warning. The thing that I'm worried about is how my own children will feel if their daycare friend stops coming to daycare. Obviously it would be hard on me to miss a daycare kid that I've gotten attached to, but I know this is business and I have to be ready for it. My own kids really enjoy the daycare kids, and I think it would be really hard on them if a kid leaves, especially without notice. Has anyone experienced this with their kids? I have a 5 year old and a 1 year old, and they each have someone in daycare that they really enjoy playing with.