  We extend our previous study of elastic pion-nucleon scattering in the
framework of chiral perturbation theory by performing a combined analysis of
the reactions $\pi N \to \pi N$ and $\pi N \to \pi \pi N$. The calculation is
carried out to fourth order in the chiral expansion using the heavy baryon
approach and the covariant formulation supplemented with a modified version of
the extended on-mass-shell renormalization scheme. We demonstrate that a
combined fit to experimental data in both channels leads to a reduced amount of
correlations between the low-energy constants. A satisfactory description of
the experimental data in both channels is obtained, which is further improved
upon including tree-level contributions of the $\Delta$(1232) resonance. We
also explore a possibility of using the empirical information about $\pi N$
subthreshold parameters obtained recently by means of the Roy-Steiner equations
to stabilize the fits.
