What is the basis for Catholics believing Jesus fell three times (or seven) on his journey to Calvary?

In reviewing the Stations of the Cross , I was surprised to learn that stations 3, 7, and 9—descriptions of three times Jesus fell under the weight of the cross he carried—are in fact not based on scripture. I also learned (here ) that some German and Dutch Catholics historically observed SEVEN falls, often citing as prophesy Proverbs 24:16: “though the just fall seven times, they rise again, but the wicked stumble from only one mishap.” Do Catholics have any historical, traditional, or scriptural basis—or any rationale—for claiming that Jesus fell under the weight of his own cross on the way to Calvary?