Why one family each?

I really liked this movie. Very heartwrenching and well done.

I was wondering why the mom was looking for separate family for each child. She mentioned a couple times that she wanted each child to have his/her own family. Was this because she really wanted them to all have separate families or just did not think there would be families who would want to adopt multiple children?

I would think that some families who wanted to adopt may be interested in adopting 2 or even 3 kids together. That would be way easier for the kids too. I know it is also very possible that no families would want to adopt multiple children by why rule it out?

It was great that the one family did decide to adopt the second child after all. I was happy to read on these boards that that was actually true (had thought it might be added to make the ending happier).