I left DS1 in day care 1 day a week while I was on maternity leave with DS2. One reason was to keep the spot. Another was to give myself a day with just one child so I could do things that needed going - one on one with the baby, errands, housework, rest etc (not all on the same day mind you!). I am so glad I did it - not only did DS2 and I love having a day of one-on-one time, DS1 loved having his own space for a day. He has always loved day care and used to look forward to his day out. I think it also did him a lot of good to get attention and time to do things himself without always having his brother to consider.