Im starting to worry about my daughters speech development. She is 16months old and only saying baba and mama. She understands everything we say to her but she just isn't trying to speak or say words. No 'hi ya' or 'oh oh'. She grunts everything and gets cross when she wants something. She has been in and out of hospital this year with virus's and chest infections so I'm worried the sickness has put her off as her chest and throat would have been sore? Should I be worried or just give her more time? Thanks :)