If you and your family were going to have your photograph taken it probably would not take that much time to arrange.
Cameras are small and photos can be taken instantly.
However, in the 19th Century having your photo taken was quite different. A photographer would come to your house to take the photograph - usually on a special occasion, like a wedding. The group would pose carefully and everyone in the photo would have to remain very still for some minutes. Look at Source 1. At first glance, it seems like just another Victorian photograph - but look again.