  Infant mortality brought about by the expulsion of a star cluster's natal gas
is widely invoked to explain cluster statistics at different ages. While a well
studied problem, most recent studies of gas expulsion's effect on a cluster
have focused on massive clusters, with stellar counts of order $10^4$. Here we
argue that the evolutionary timescales associated with the compact low-mass
clusters typical of the median cluster in the Solar neighborhood are short
enough that significant dynamical evolution can take place over the ages
usually associated with gas expulsion. To test this we perform {\it N}-body
simulations of the dynamics of a very young star forming region, with initial
conditions drawn from a large-scale hydrodynamic simulation of gravitational
collapse and fragmentation. The subclusters we analyse, with populations of a
few hundred stars, have high local star formation efficiencies and are roughly
virialised even after the gas is removed. Over 10 Myr they expand to a similar
degree as would be expected from gas expulsion if they were initially gas-rich,
but the expansion is purely due to the internal stellar dynamics of the young
clusters. The expansion is such that the stellar densities at 2 Myr match those
of YSOs in the Solar neighborhood. We argue that at the low-mass end of the
cluster mass spectrum, a deficit of clusters at 10s of Myr does not necessarily
imply gas expulsion as a disruption mechanism.
