Secular evolution of the eccentricity of the inner planet of a pair whose orbits have been integrated with and without the GR term. The semimajor axis of the inner planet is a₁ = 0.1 au while its eccentricity is set to e₁ = 0.15 and e₁ = 0.3 in the two different cases. The outer planet has a₂ = 1.5 au and its eccentricity is e₂ = 0.1. The mutual inclination is initially set to 3°. Tidal forces are not included in these models.