I take 4 weeks a year. 2 weeks in the summer and 2 weeks at Christmas/New Year's. My clients do not pay for this time and if a stat holiday falls during my holiday I tell my clients they don't need to pay.
4 weeks may seem generous, but I use this time to vacation, reboot, do some daycare paperwork, freshen the daycare area etc. The point is it is time off from the routine of the daycare and I always feel better afterward. I can't imagine not taking a break. I haven't had a sick day (knock on wood) in years and don't take personal days so my clients don't complain and if they did............my mental and physical health comes first!