Given: in $\triangle ABC$, $E$ and $D$ are points defined in sides $AC$ and $BC$, respectively. $AF$ bisects $\angle CAD$ and $BF$ bisects $\angle CBE$
Prove: $\angle AEB+\angle ADB=2\angle AFB$
I started with a draft of the problem for better visualization.

My strategy was to show that $\angle AFB$ can be constructed by the sum of 1/2 of angles $\angle AEB$ and $\angle ADB$. But after many attempts I'm not finding the answer.
Hints and solutions are welcomed. From a material with questions for math contests.
$$\angle{AEB}+\angle{ADB} = 2\pi - \angle{EAB} - \angle{DBA} - \angle{EBA} - \angle{DAB} = 2(\pi - \angle{FAD} - \angle{DAB} - \angle{EBA} - \angle{FBE}) = 2(\pi - \angle{FAB} - \angle{FBA}) = 2\angle{AFB}$$