Must be something in the cosmos a'brewing. My S4 said something similar to me in the car after I picked him up from preschool yesterday. First he said that he misses his Mommy. He had just spent the night with W on Monday night (W keeps him for just the evening while I take his older brother to cub scouts -- but sometimes S4 wants to stay the rest of the night with his mother instead of coming back with me and S7.) He was thus intimating that he wanted to stay with W again,
So in response to S4's whine about missing his mother, I told him that I always miss him too when he stays with Mommy instead of me.
S4's response was to say he wants Mommy and Daddy together again. I started to get a little choked up. But I held it together and then concluded for S4 that that would be really nice but it's just not going to happen, sad to say.