This could be a series or a movie, maybe 15-20 years old.
A mother with kids tries to find an apartment to rent. She isn't well off and could only afford a place where kids aren't allowed. What she does is, she smuggles in the kids, with the help of a male accomplice, who hides them under his coat.
The landlord is and old lady. The kids have to be very silent all the time to avoid somebody discovering them.
But once the old woman spots them as they are looking at her through a window.
Could be foreign.
It's not Nobody Knows.