It may seem weird, but I've had this happen to me too. Got a call on a friday that they needed childcare to begin on the Monday. I agreed to meet with them on the Sunday as I was curious and they ended up being one of my favourite families :) Ended up that the rush for daycare was because the Mom was offered to go back from mat leave early to a higher paying/position job and they hadn't done the daycare search yet as she technically wasn't supposed to go back until 2 months from then. Maybe the family who contacted you is in a similar situation. Just trying to add positive and hope they are not some crazy family who has been kicked out of other daycares lol :)

