Usually it's a case of pollination. If the flowers were pollinated by another suitable Aesuculus tree, then the fruit develop to maturity. But if the flowers either weren't pollinated, or were unsuccessfully pollinated by an incompatible Aesculus, then the fruit would either initially look like they are developing only to drop off soon afterwards. This happens a lot with Magnolias and Oaks. They will hold on to their fruit, and the fruit will even look to be developing, but then sometime before maturation, they will drop the developing fruit(Magnolias do this 4 to 6 weeks after flowering and Oaks will do this as long as 3 or 4 months after flowering) because the flower wasn't properly pollinated. I suspect that since you have all the same cultivar they are probably not self compatible enough to properly pollinate their own flowers and hence the fruit are dropped. Since they are all the same cultivar, they are all genetically identical, so any pollen landing on any flower would be the same as if the pollen from one lone tree landed on it's own flowers. Plant another variety of Red Horsechestnut (Aesculus x carnea), like 'Briotii or 'O'neill', or perhaps even one of it's parents(A. hippocastanum or A. pavia) and you should get some fruit, although some claim at least some Red Horsechestnuts are sterile.

I might rethink planting a type 2 clem on a Harry Lauder. One of the pleasures of the HL is its winter silhouette with interesting branch shapes. Type 2 clems aren't usually cut to the ground in winter (you can do it, but will lose all the first bloom, and some won't bloom as well in the second bloom in my cold zone 5.) If you don't cut it to the ground you will have all the scrappy dead vines left in your winter HL which will interfere with its bare-branched silhouette. At least consider a type 3 or choose your type 2 carefully so that you get one of them that seems to bloom longer so you won't lose too many blooms. My Daniel Deronda, a type 2, will bloom almost all growing season, even after it has winter killed to the ground, and I imagine that there may be some more. I mostly put type 1s and 2s where I don't have to see the dead vines in winter. The other thing to consider is the ultimate size of the clematis and the HL. A large, fast-growing clematis can overwhelm a young or small shrub. I tried the strategy of planting clems on the opposite side of the shrub from where I want to eventually view them so that they would grow through, and I find that I prefer the ones where I planted them on the side from which I wanted to view it. The grow up the shrub just fine in my garden. It may be a difference in sun angle and intensity between Bob's CA location and my NH location.

Wow, you found a nest !? That's very special. I received an email photojournal of a hummer nest and babies hatching a while back - will look for it again and post it here if I can find it. Meanwhile, two years ago I was treated to the sight of a hummer Mom and three hummer babies at my butterfly bush. Had my son not seen it too, I would have imagined I was seeing things ! They are so very special, precious and fragile.

I had a couple of pink flamingos in my yard for awhile. I named them 'Tongue' and 'Cheek'. They finally died. I think of,embarrassment.