We theoretically investigate the interplay between local lattice distortions around $rm{Mn^{2+}}$ ion impurity and the ions magnetic polarization, mediated through spin-orbit coupling of hole. We show that the tetrahedral symmetry around $rm{Mn^{2+}}$ ion impurity is spontaneously broken even in the paramagnetic regime. Modest local lattice distortions around the impurity $rm{Mn^{2+}}$ ion, along with the growth strain, stabilize magnetization along $< 110 >$ directions, in the ferromagnetic regime. We explain the experimentally observed in-plane uniaxial magnetic anisotropy seen in this system using this symmetry-breaking mechanism.
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