Why are ileostomy bags following me?

At the weekend I had a pleasant evening making videos and discovering new blogs that I haven't read before.  My partner was getting up with our little one in the morning, so I didn't need to get to bed any time soon.

And then I notice something about the adverts dotted around the pages that I'm visiting.

They're all about ileostomy bags.

Let me say right now that I have nothing against ileostomy bags, if you've had that procedure then obviously you need the bags.  But I haven't (and have no immediate plans to).  What does Google know that I don't?