Once a child goes to school and their sibling remains in daycare, there are already two different care situations so I never even gave it a second thought when I stopped taking SA kids.
I never lost a single family when I made the change and most totally agreed with me when I explained that SA kids really didn't fit in too well with little ones and vice versa.
I started out with taking only the SA kids that had siblings here but that quickly became a PITA so I just drew the line and stopped taking them once they hit Kindergarten.
BEST move I ever made!
