I am a periodic sufferer of a condition. Since I can find no official name for this complaint, I am going to name it myself. My problem is called Empty Stroller Syndrome.
Empty Stroller Syndrome (ESS) occurs almost exclusively in fathers of young children. It manifests itself in well-populated areas, including public transportation. A bout of ESS is generally brought on when the mother takes the child from the stroller to some location disassociated from the father, who is left with an empty stroller and no child in sight.
It is important to note that if you are out in public with an empty baby stroller, but have no children in your life, you are not suffering from ESS. You are suffering from being one weird dude.

ESS is an often misunderstood condition due to the fact that, to the unfamiliar observer, the sufferer closely resembles the weird dude aforementioned. Lacking a nearby baby, there is no recognized protocol for differentiating the ESS sufferer from the weird dude.
It dawned upon me that I suffered from ESS while I was riding the metro train in Washington, D.C. With two small children, we have many accessories to carry with us on outings. These many necessities were secreted in and about our stroller, with heavy baggage hanging from each handle.
Every time we boarded the train, my wife took the baby out of the stroller and held him on her lap. When we could sit together, this presented quite a natural scene. But on the D.C. subway, parties often need to disperse, transforming me into a solitary man with his heavily weighted stroller.
Judging from the looks I received from fellow passengers, some sympathetic men recognized, or at least hoped they recognized, an all too familiar case of ESS. Other passengers merely wondered silently about that weird dude who used a baby stroller as a pushcart for his sundry, joyless bundles.
Without the baby in place, the stroller was unbalanced. At every change in momentum, it was liable to tip over backward. Not wanting to risk injuring others, I guarded it closely. This made me look less the innocent victim of a crowded transport system, and more the weird dude whose precious, precious collections of plastic spoons and acorns must be jealously protected from a covetous world.

In most cases, it doesn’t matter to me what strangers think. But I’ve put a lot of work into this fathering business, and I’d rather not be thought of as some kind of unhinged stroller pervert. I have the children to prove that there is a perfectly reasonable pathology behind my distant, glassy stare. They are elsewhere on the train, with their mother, the one competent to be the guardian of cargo more important than empty strollers.
I tried to ease the suspicions of my close companions by turning and yelling things to my family that hinted at more than a passing acquaintance between them and myself. I gave up this tactic when it became clear that the crowd did not relish a loud conversation about the probability of there being a poopy diaper somewhere among them. For those who could not see the family to whom I was speaking, this talk only added to my mystique.
Alas, there was nothing to do but quietly endure my flare-up of Empty Stroller Syndrome. In the distance, I could hear people clucking over the baby. Nobody ever gushes about how adorable my empty stroller is. In silence, they avoid making eye contact with me.