God I feel so guilty. Today is the first time I've looked underneath the flip-up spout of our Tommee Tippee cups and I can't believe I've been letting my DCs drink from them. Absolutely clogged with black slimy cack in the stupid narrow holes - really, really disgusting. I'm surprised it hasn't made them ill.
Of course I've always washed them, using really hot soapy water and a scrubbing brush. But you can't get under that flip-up bit properly so I thought flushing it through with water was good enough. It's only because I saw some black strain sticking out that I took a knife to it to lever the spout off. Probably I'm a total slattern and everyone else knows to pop that bit off and clean it somehow. Why's it so badly designed??