As a third child my youngest son tends to get the short end of the stick. With an older brother and sister he tends to get toys that are second or third hand and it is a struggle to get him things that are just his and not immediately stolen by his older siblings. Of course money too plays its part. Although I may have the will to get him a new toy just for him I usually have something similar already and of course no matter how babyish the toy is as soon as I liberate it from the back of the cupboard for my 2 year old it is immediately grabbed by older sister (8) or brother (6) with cries of "I remember this!" and cue the 2 year olds temper tantrum.
This is the start of resources that are produced for B first to redress this balance. It is the kind of thing used by daycare for their "sensory table" and since we are in Germany and don't have access to an English-speaking parent and toddler group at the moment (I am ashamed to say my German is woeful) he hasn't had much opportunity to experience this kind of thing outside the home either. This is not to say that he doesn't get to play with sensory toys like sand and water but anything else tends to be a bit ad hoc. Bottles like these can be made cheaply and stored away and got out to play with like any other toy.
This first one is the easiest - water coloured with food colouring and baby oil with the top hot-glued on. If you want to give it a fancy name you can call it your "wave bottle" or "ocean bottle".
Others will follow as an when they become available (I'm planning to use the bottles from the little bottles of juice that go in the older kids lunches for school and the "table clearers" tend to be a little over enthusiastic about collecting recyclables!).
Of course the best laid plans can go wrong. When I came to take the photo where did I have to liberate it from? DD's bedroom of course!