Star cluster complexes such as the Carina Nebula can have formed in turbulent giant molecular clouds . We perform a series of N -body simulations starting from subclustering initial conditions based on hydrodynamic simulations of turbulent molecular clouds . These simulations finally result in the formation of star cluster complexes consisting of several subclusters ( clumps ) . We obtain the inter-clump velocity distribution , the size of the region , and the mass of the most massive cluster in our simulated complex and compare the results with observed ones ( the Carina Nebula and NGC 2264 ) . The one-dimensional inter-clump velocity dispersion obtained from our simulations is 2.9 \pm 0.3 and 1.4 \pm 0.4 km s ^ { -1 } for the Carina- and NGC 2264-like models , respectively , which are consistent with those obtained from Gaia Data Release 2 : 2.35 and 0.99 km s ^ { -1 } for the Carina Nebula and NGC 2264 , respectively . We estimate that the masses of the parental molecular clouds for the Carina Nebula and the NGC 2264 are 4 \times 10 ^ { 5 } and 4 \times 10 ^ { 4 } M _ { \odot } , respectively .