Finicky eater with food allergies!

[MomaBunny70]

My 2 1/2 yr old son, F, can't have dairy or soya milks of any sort. Consequently he's been on Neocate LCP since 10 weeks old. As he's older now, I mix his supper bottle as half & half of neocate & coconut milk. He's not quite old enough for coconut (& other alternatives) milk.
Strictly speaking F doesn't really need a 10pm supper feed, BUT... he can be very finicky with the foods he can eat (can't have wheat & gluten either) hence still having a supper feed.
Whilst we are encouraging F to eat more veggies (he loves fruit), we want to get the extra bulk into him. F is quite lean & growing well.
I was putting baby rice in his neocate/coconut milk but the rice seems to upsetting his tummy & he gets a bit hyperactive!
Any suggestions what I can bulk his supper milk with? I mixed in a bit of well-blitzed gluten-free porridge last night & he enjoyed that but it would be nice to have other alternatives to mix the flavours about a bit.
Thanks for reading... 🙂

[Slinkyminky22]

If it were me I would give him a bowl of porridge made with oat/almond/rice/coconut milk for supper. Rather than mixing in a bottle. Can't he switch to a cup at 2.5yo? If not, a bottle of milk alternative along with the porridge would be fine. As far as I knew, milk alternatives were basically suitable from 12mo. I know some are more nutritious than others though.

Edit: if supper must be a drink, what about a smoothie type thing with milk alternative, banana, oats, spinach etc.