The orthoperovskites TbCoO3 and DyCoO3 with Co 3+ in a non-magnetic low-spin state have been investigated by neutron diffraction down to 0.25 K. Magnetic ordering is evidenced below TN = 3.3 K and 3.6 K, respectively, and the ordered arrangements are of canted type, AxGy for TbCoO3 and GxAy for DyCoO3 in Bertaut's notation. The experiments are confronted with the first-principle calculations of the crystal field and magnetism of Tb 3+ and Dy 3+ ions, located in the P bnm structure on sites of Cs point symmetry. Both these ions exhibit an Ising behavior, which originates in the lowest energy levels, in particular in accidental doublet of non-Kramers Tb 3+ (4f 8 configuration) and in ground Kramers doublet of Dy 3+ (4f 9 ) and it is the actual reason for the non-collinear AFM structures. Very good agreement between the experiment and theory is found. For comparison, calculations of the crystal field and magnetism for other systems with Kramers ions, NdCoO3 and SmCoO3, are also included.