We study the $^{6}_{\Lambda\Lambda}$He and $^{10}_{\Lambda\Lambda}$Be hypernuclei in the three- and four-body models, respectively, employing harmonic oscillator bases and presently most realistic alpha-alpha, alpha-lambda and lambda-lambda interactions. In order to improve convergence we use correlation functions in the case of $^{10}_{\Lambda\Lambda}$Be. Comparison is made with results obtained using similar interactions and other methods, and it is performed an analysis concerning the possibility of a unified description of both hypernuclei.