Stuck in Chapter 6 (Mirrors Room) can someone give me some hint?

[baka.cdaz]

I alway love the puzzle of this game but this puzzle gotta drive me crazy.
All I can do is push the switch randomly and I Ivy start to shake her head like a Rock star.

I read a walkthrough Gameboomer it say "Using the clue on the wardrobe"
but Susan keep said it noting special.

So what is the clue on the wardrobe? I can't see anything change on waredrop when I push the switch.

Sorry if there are alredy another post about this but i can't find it.

[Priest of Syrinx]

Handprints on the walls in bedroom

[baka.cdaz]

Thankyou very much. ♪

[✪Old Man Jenkins'̏̏̏̏̏̏]

For those that keep saying they wanted "more/some backstory for Joe + Ivy Davis", PLAY DOWNFALL!!!
It's basically this game's prequel
D/L for FREE: DOWNFALL + OST; 100% FREE[screen7.co.uk]
Also, game is being REMADE in the style of The Cat Lady! It has been GREENLIT FOR STEAM! Yay!