I've got a Hauck Alpha highchair, (a bit like the Tripp Trapp but cheaper) but it is a little bit too low for my nearly-6-month-old DS to reach the table comfortably, i.e. he will have to reach up for food. I just need to raise the highchair by about 1-2 inches then it will be a lot more comfortable. I can't raise the height of the actual seat bit nor can I put something else on the seat, as he has such chubby legs, he wouldn't be able to get in! I thought of those cot blocks that you raise a cot with but I don't think the highchair legs will fit in them as they're larger and slanted. Any safe ideas?