saying bad things to your baby

in my case, its not my MIL but my BIL tenant. she like to ask for my baby and talk nonsense like 'why? mummy never give you milk that's why cry isit?' or 'mummy beat you isit?' im so annoyed like why in the world do you have to say those nonsense and untrue things. she made me into a bad mummy right infronf of my baby. jeez i feel so sad that i told my hubby and lessen my time outside of my room