Hi Freezing, toys I've got for my youngest two (ds4 and dd26 months) now and in the past that I like (as opposed to hiding cause they're awful):
No 1 is definitely My Pal Scout. They grow with the child and my 4yo still likes his now. You can personalise songs and favourite colour/food/animal. It will also say and spell his name.
Also like: toot toot animals, but not too many as the songs get annoying together. Good size for little hands and very robust.
London bus with characters. Sturdy enough to sit on and my dd likes putting the figures in and driving it around.
Not very seasonal, but dd got this waterplay for her birthday (my 8yo also liked playing with it). You can put the pieces together several different ways and you can buy add ons too.
!!! at the price, but if you can find this any cheaper, it's a great toy that I think was bought for my 8yo. Very very robust (think throwing down the stairs) and not very annoying. Must not be made any more though seeing the price - ebay 2nd hand?
Got this house for dd last christmas. Lots of things to do on it - buttons, switches, sliders etc. Does a lot of opposites and quite popular here.
Noisy books, but not too loud. We've got the duck one of these as well.
I'll be back if I can think of more 
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