Anybody knows, where can I get matching clothes for Mum, dad and baby girl in Singapore ?

You can try online shopping Qoo10.sg, carousel, Facebook page like toddleythoughts123. There are many wide array of designs to choose from. Otherwise, you can try mothercare and also push carts at bugis. I only saw one retail shop at Jurong point selling too. Cant remember the retail shop name but its just beside carl's junior burger. Happy Shopping!