That is a bold faced lie.
Drop the soap.
Drop it often.
Especially when your mother-in-law is visiting and has taken the kids downstairs so you can sleep in for once in your life. When you both decide that a shower together sounds like the perfect way to wake up.
Honestly, just throw the soap at that point (don’t hit him, he won’t like that). You won’t need the soap. Nothing cleans you off like a first thing in the morning shower fuck.
I’m practically squeaky.