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This talk is dedicated to the most recent measurements of the processes thatfeature the production of a top quark pair either with an electroweak standardmodel boson, or another pair of top, bottom or light quarks. For themeasurement of the production cross-section of top quark pair in associationwith a photon, 19.7 $\rm fb^{-1}$ of proton-proton collision data collected byCMS detector at $\sqrt{s}$ = 8 TeV is used, while for four top production, $\rmt\bar{t}$ + bb, $\rm t\bar{t}$ + jj, $\rm t\bar{t}$W and $\rm t\bar{t}$Z thedata collected at $\sqrt{s}$ = 13 TeV amounting to 35.9 $\rm fb^{-1}$, is used.The measurement of $\rm t\bar{t}\gamma$ is performed in the fiducial phasespace corresponding to the semileptonic decay chain of the top quark pair, andthe cross section is measured relative to the inclusive top quark pairproduction cross section. The fiducial cross section for this process is foundto be 127 $\pm$ 27 (stat + syst) fb. The most recent search for the four topquark production, that explores the same-sign dilepton final state, set theupper observed (expected) limit to 4.6 ($2.9^{+1.4}_{-0.9}$) times predictedstandard model cross section. The measured cross section of the top pairproduction with two b quarks is found to be $\sigma$($\rm t\bar{t}$ + bb) = 3.9$\pm$ 0.6 (stat) $\pm$ 1.3 (syst) pb in the full phase space. The measurementof the $\rm t\bar{t}$W and $\rm t\bar{t}$Z processes combines three finalstates with two same-sign, three and four leptons. The $\rm t\bar{t}$W and $\rmt\bar{t}$Z production cross sections are measured to be $\sigma$($\rmt\bar{t}$Z) = $\rm 1.00^{+0.09}_{-0.08} (stat.)^{+0.12}_{-0.10} (sys.)$ pb and$\sigma$($\rm t\bar{t}$W) = $\rm 0.80^{+0.12}_{-0.11} (stat.)^{+0.13}_{-0.12}(sys.)$ pb with an expected (observed) significance of 4.6 (5.5) and 9.5 (9.9)standard deviations from the background-only hypothesis.

Studies of $\rm t\bar{t}$+X at CMS