My ds first caught a tummy bug of my older boy when he was 9 months old, it lasted about 5 days, 2 weeks later he got another. 4 weeks later and he has started with vimiting again all evening / night. This time he keeps pulling a face like he's tasted something nasty in his mouth. Can baby's get stomach acid? He also threw up bright yellow sick earlier too. Or has my poor ds got the dreaded tummy bug again? What am u doing wrong? The first time he got it my 4yr old had it first, 2nd time we were all fine and now everyone us ok (touch wood). Any idea