First time that Victor manages to bust through the knees of a pair of his pants. I guess there was no big surprise there considering how much crawling a toddler experiments throughout a day. He started walking a while ago but still he prefers to crawl now and then on short distances.
I made these whale-shaped patches and used fusibale web to attach them to the pants. In case they come off at washing (which I really doubt as I've used this technique before on my clothing) I'll use hot glue next time.
Here are some other fun patches to get you inspired.