Where's my Mummy?

I took a drive SW of Calgary yesterday evening, wanting to check on Mountain Bluebirds. I was relieved to find that this little family seemed OK after all the rain and flooding we've had recently and especially this past week. Two of the baby Bluebirds were trying to look out on to the big wide world, so I know that at least there are two that are just fine. There was no sign of Mom anywhere, though, which was most unusual. It was only Dad who kept flying back to the nest box with food. I do hope the mother is OK. Maybe she was just taking a much-deserved nap somewhere.