I also saw one of the stray cats, Gremlin, acting frantic near the front porch yesterday, and meowing in a peculiar way. So I went to investigate. From underneath the wooden porch came the sound of very young kittens crying for mama. So we're back to meows beneath our feet. (I thought I had this area sealed off. I guess I was mistaken.)
By the way, those trunks in the pictures belong to lilacs. Every other place I've lived, it is the custom to remove a quarter to a third of the older shoots every year in lilac bushes, to keep them forever young and bushy. Around here, the custom is to prune off everything but a handful of the oldest branches, and train the lilacs into multi-trunked trees. I don't know how old these are, but they certainly go back decades.