  The cat state is shown to `store' a single photon through the superposition
of its orthogonal counterpart with itself, and an excited oscillator state.
Photon addition leads to a $\pi $ phase shift at origin in the observed phase
space interference of the Wigner function, which also displays negativity,
controlled by the average photon number ($|\alpha|^2$) of coherent states
comprising the cat state. The maxima and minima of the sub-Planck tiles in the
phase space of the kitten state are interchanged after photon addition, leading
to their orthogonality. Interestingly, photon addition to Yurke-Stoler state
characterized by Poissonian statistics leads to a sub-Poissonian distribution.
