Let P be the statement: Every subset of plane belongs to the sigma algebra generated by $\{A \times B : A, B \subseteq \mathbb{R}\}$.
Let Q be the statement: Every sigma algebra on $\mathbb{R}$ of size at most continuum is generated by a countable family.
Both statements are independent of ZFC and P implies Q. Does Q imply P?
This stems from the following question.