Why is sharing a photo stream taking so long

I Use shared photo streams to share photos with daughter. A weeks ago I tried to share a series of about 2 doz. birthday pics using an existing shared photo stream. I checked after sharing and saw no activity. I redid the sharing thinking I had not pressed all the keys needed. A day later and still no activity. Tried to share again. Hours later, I tried again. After a week of trying, I gave up. Today I added 3 pics to a stream shared by me and wife. I saw immediate sharing. Tried to share a new set of photos with daughter. Nothing appeared to happen, but I did see those birthday photos had been added, 5 X. In fact, daughter just told me she just received notification about the birthday sharing today, even though the first sharing attempt was over a week ago. Am I missing something? What does it take for sharing photo streams to work properly and in a timely fashion?