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The LHCb collaboration newly measured the decay rate of doubly charmed baryon$\Xi^{++}_{cc}\to\Xi^{'+}\pi^+$ and a ratio of its branching fraction withrespect to that of the decay $\Xi^{++}_{cc}\to\Xi^{+}\pi^+$ is reported as$1.41\pm 0.17\pm 0.10$. This result conflicts with the theoretical predictionsmade by several groups. In our previous work, following the prescription givenin early literature where the $us$ diquark in $\Xi^{+}_{c}$ is assumed to be ascalar whereas in $\Xi^{'+}_{c}$ is a vector i.e. the spin-flavor structure of$\Xi^{+}_{c}$ is $[us]_0 c$ and that of $\Xi^{'+}_{c}$ is $[us]_1 c$, westudied the case of $\Xi^{++}_{cc}\to\Xi^{(')+}$ with the light front quarkmodel. Numerically we obtained$\Gamma(\Xi^{++}_{cc}\to\Xi^{'+}\pi^+)/\Gamma(\Xi^{++}_{cc}\to\Xi^{+}\pi^+)=0.56\pm0.18$which is about half of the data. While abandoning the presupposition, wesuppose the spin-flavor structure of $us$ in $\Xi^{+}_{c}$ may be a mixture ofscalar and vector, namely the spin-flavor function of $\Xi^{+}_{c}$ could be${\rm cos}\theta\, [us]_{0}[c]+{\rm sin}\theta\, [us]_{1}[c]$. An alternativecombination $-{\rm sin}\theta\,[us]_{0}[c]+{\rm cos}\theta\, [us]_{1}[c]$ wouldcorrespond to $\Xi^{'+}_{c}$. Introducing the mixing mechanism the ratio$\Gamma(\Xi^{++}_{cc}\to\Xi^{'+}\pi^+)/\Gamma(\Xi^{++}_{cc}\to\Xi^{+}\pi^+)$depends on the mixing angle $\theta$. With the mixing scenario, the theoreticalprediction on the ratio between the transition rate of$\Xi^{+}_{cc}\to\Xi^{'+}_c$ and that of $\Xi^{+}_{cc}\to\Xi^{+}_c$ can coincidewith the data as long as $\theta=16.27^\circ\pm2.30^\circ$ or$85.54^\circ\pm2.30^\circ$ is set. Definitely, more precise measurements onother decay portals of $\Xi^{+}_{cc}$ are badly needed for testing the mixingmechanism and further determining the mixing angle.

Revisiting the transition $\Xi^{+}_{cc}\to\Xi^{(')+}_c$ to understand the data from LHCb