Robins again

What is it with these Robins? At least the last time, they built their nest in a somewhat safe location, about 9 feet off the ground. This time they chose the top of a 6 foot ladder that was propped up against a fence. I'm thinking it would be pretty easy for one of the many neighborhood cats to climb said ladder. Not sure if I'll go to jail for this, but yesterday I removed the ladder, and carefully secured the nest in a "box" of sorts, made of lumber scraps screwed together. I'm speculating she must have approved, for today, look what I discovered...one new blue egg...only time will tell if my efforts are in vain...Happy Mother's Day Mrs. Robin :)